Saturday, 7 February 2026

e-day and Andy Jackson

 

Adding on to the post about coincidences earlier, this post is about a value derived from the same hyperbola, y=1/x. For the mathematician, February 7th, (or 2 - 7) is the date we decide to celebrate the constant which is the base of the natural logarithms, appx 2.71828.... (more later, and a way to memorize it).

 There have been LOTS of sites that explain LOTS of things (such as at Homeschool Math Blog and here at Let's Play Math.) about the value e, so I will try to not be too redundant and throw in something totally different, as the Monty Python folks used to say... 

The letter e was first used for the base of the natural or hyperbolic logarithms by Leonhard Euler. Earlier I had mistakenly thought that Euler was the discoverer of the value, but in fact the number was published in Edward Wright's English translation of Napier's work on logarithms in 1618, almost 100 years before Euler's birth. [and in fact, it was known to the English Mathematician Roger Cotes. Cotes is one of those many promising mathematicians who died at a young age and Newton, who seldom said anything good about anyone else, once said "Perhaps if Cotes had lived, we would have known something"..] The number represented by e is approximately 2.718281828459045... Euler actually computed the number to eight more decimal places. This was done in 1727, and would seem almost impossible accuracy for anyone else, but of Euler it was said, "Euler calculates as other men breathe." 

It was known from the work of Gregory of St. Vincent and others that the logarithms were somehow linked to the area under the hyperbola f(x)=1/x because the area under the curve matched the logarithmic property Log(AB)= Log(A)+Log(B). The Area under the curve from 1 to x=ab is equal to the areas from 1 to x=a plus the area from 1 to x=b. The value of e is such that the area under the hyperbola from 1 to e is 1 square unit. It has been conjectured that Euler may have used e as an abbreviation of the word Eins, the German word for one. 

One oddity that students and teachers may use to remember the first 15 digits of e, given above, is to recognize their relationship with Andrew Jackson's presidency and an isosceles right triangle. Confusing? Just wait, all will be clear. We begin with 2, because Jackson was president for two terms. The 7 tells us he was the seventh president of the US. 1828 is the year he was elected, and we repeat this because of the two terms. Then we give the three angles of an isosceles right triangle, 45, 90, 45, and we have completed 15 digits of the base of the natural logarithms. I am almost 100% sure I picked that up from one of Martin Gardner's Scientific American columns.

Euler was one of the most influential mathematicians of the period and his prestige was sufficient that his use of a variable often marked it for posterity, but there were other symbols that were suggested occasionally. D'Alembert used c for the same constant in 1747, and Benjamin Peirce suggested a symbol that looked like a paper clip, or the @ symbol now used for e-mail addresses instead of pi, and the same symbol reflected in a vertical line for e. 

But now I have to bring up the fact that in my new home town of Paducah, Ky, e-day is for Engineers Day. The University of Kentucky College of Engineering has a branch campus at Paducah, and they are having their open house on February 21 at Crounse Hall. They have, among other things, an Edible car contest  (would I kid you?) as well as an Egg Drop contest, A Popsicle Stick bridge contest, and of course (drum roll please...) A Duct Tape Challenge...... I had a student only a few years ago who was a master of duct-tape-utilization. He would make roses out of duct tape to impress the ladies, (and did) and had a duct tape wallet... and once came to school in a sport coat made entirely of duct tape... I imagine he could have had one in cashmere for about the same price.

On This Day in Math - February 7

  

The Frenet-Serret Frame, *Wik



A mathematician, like a painter or a poet, is a maker of patterns. If his patterns are more permanent than theirs, it is because they are made with ideas. Beauty is the first test: there is no permanent place in the world for ugly mathematics.
~Godfrey Harold Hardy


The 38th day of the year; 31415926535897932384626433832795028841 is a prime number.  BUT, It’s also formed by the 18th and 19th digits of pi.

38 is the largest even number so that every partition of it into two odd integers must contain a prime.

38 is the sum of squares of the first three primes \(2^2 + 3^2 + 5^2 = 38 \). *Prime Curios

At the beginning of the 21st Century there were 38 known Mersenne Primes. As of this writing, there are 52, the last,  2^(136,279,841) − 1, discovered in October 2024 ..


Although we've had some unusual shaped flags, usually the star field is in a rectangle with the stars displaying some kind of (generally rectangular) similarity. Some have strayed greatly from the rectangle form however. This one with 38 stars from 1877 until 1890 is an example.


38 is also the magic constant in the only possible magic hexagon which utilizes all the natural integers up to and including 19. It was discovered independently by Ernst von Haselberg in 1887, W. Radcliffe in 1895, and several others. Eventually it was also discovered by Clifford W. Adams, who worked on the problem from 1910 to 1957. He worked on the problem throughout his career as a freight-handler and clerk for the Reading Rail Road by trial and error and after many years arrived at the solution which he transmitted to Martin Gardner in 1963. Gardner sent Adams' magic hexagon to Charles W. Trigg, who by mathematical analysis found that it was unique disregarding rotations and reflections.

*Wik



EVENTS

In 1812, the third day of powerful earthquakes struck, this one with an epicenter near New Madrid, Missouri, part of a three-month series in the central Mississippi River valley, known as the New Madrid earthquakes that began on 16 Dec 1811. The first two had happened on that December day, six hours apart, each with an epicenter in northeastern Arkansas, and were felt hundreds of miles away. Another followed on 23 Jan 1812, with epicenter in the far southeast corner of Missouri. All were powerful, about magnitude 7-7.5, with many aftershocks. Contemporary accounts tell of houses damaged, chimneys toppled, remarkable geological phenomena and landscapes changed. They remain among the most powerful earthquakes in the United States. The New Madrid fault remains a concern. *TIS (especially to those of us who live not far away near Possum Trot, Ky.)

1877 artist's impression of the 1811 New Madrid earthquake in a woodcut illustration for the book Our First Century by R.M. Devens. And mapping of the fault zone







1885 On this day in 1885, David Hilbert defended two propositions in a public disputation at the University of Königsberg. One of Hilbert's chosen propositions was on physics, the other on philosophy. This was the final stage of his doctorate, which was then duly awarded.
Hilbert promoted to Ph.D. He defended Kant's statement that man possesses, beyond logic and experience, certain a priori knowledge * Constance Reid, Hilbert, p. 16






In 1896, radiology began in England when X-rays were first used to discover the location of a bullet in a 12-yr-old boy's wrist who shot himself the previous month. When the pellet could not be found on probing, surgeon Sir Robert Jones had been consulted. Jones, having heard about the recently discovered X-rays, asked Oliver Lodge, head of the physics department at Liverpool University, if he could help with the new X-rays. On this day, the boy was brought to Lodge's laboratory. The pellet was identified embedded in the third carpo-metacarpal joint. Jones and Lodge reported the case in The Lancet on 22 Feb 1896. Charles Thurstan Holland who had been in attendance subsequently pioneered in clinical radiological examinations.*TIS

In 1932, the "neutron" was described in an article in the journal Nature by its discoverer, James Chadwick, who coined the name for this neutral particle he discovered present in the nucleus of atoms. He was an English physicist who studied at Cambridge, and in Berlin under Geiger, then worked at the Cavendish Laboratory with Ernest Rutherford, where he investigated the structure of the atom. He worked on the scattering of alpha particles and on nuclear disintegration. By bombarding beryllium with alpha particles, Chadwick discovered the neutron for which he received the Nobel Prize for Physics in 1935. He led the UK's work on the atomic bomb in WW II, and was knighted in 1945.*TIS




1956 Doug Ross Presents Gestalt Programming at the Western Joint Computer Conference in Los Angeles. Ross had experimented with the programming while working for the Air Force and Emerson Electric Co. *CHM

1975 Hungary issued a stamp commemorating the bicentenary (they were two days early) of the birth of Farkas Bolyai (1775–1856). [Scott #2347] *VFR


2015 A Mathematician wins an Oscar, FOR MATH. Robert Bridson, an adjunct professor in computer science at the University of British Columbia, was recognized for "early conceptualization of sparse-tiled voxel data structures and their application to modelling and simulation,".
Bridson is being honoured for his ‘pioneering’ work in developing the algorithms and code behind fluid and smoke simulations used in a long string of major movies, including The Hobbit, Gravity and The Adventures of Tintin.






BIRTHS

1816 Jean Frenet (7 Feb 1816 in Périgueux, France - 12 June 1900 in Périgueux, France) was a French mathematician best remembered for the Serret-Frenet formulas for a space-curve *SAU (Vector notation and linear algebra notation currently used to write these formulas was not yet in use at the time of their discovery.)




1824 Sir William Huggins (7 Feb 1824; 12 May 1910 at age 86) English astronomer who explored the spectra of stars, nebulae and comets to interpret their chemical composition, assisted by his wife Margaret Lindsay Murray. He was the first to demonstrate (1864) that whereas some nebulae are clusters of stars (with stellar spectral characteristics, ex. Andromeda), certain other nebulae are uniformly gaseous as shown by their pure emission spectra (ex. the great nebula in Orion). He made spectral observations of a nova (1866). He also was first to attempt to measure a star's radial velocity. He was one of the wealthy 19th century private astronomers that supported their own passion while making significant contributions. At age only 30, Huggins built his own observatory at Tulse Hill, outside London *TIS



1877 Godfrey Harold "G. H." Hardy FRS (7 February 1877 – 1 December 1947) was an English mathematician, known for his achievements in number theory and mathematical analysis.
He is usually known by those outside the field of mathematics for his essay from 1940 on the aesthetics of mathematics, A Mathematician's Apology, which is often considered one of the best insights into the mind of a working mathematician written for the layman.
Starting in 1914, he was the mentor of the Indian mathematician Srinivasa Ramanujan, a relationship that has become celebrated. Hardy almost immediately recognized Ramanujan's extraordinary albeit untutored brilliance, and Hardy and Ramanujan became close collaborators. In an interview by Paul Erdős, when Hardy was asked what his greatest contribution to mathematics was, Hardy unhesitatingly replied that it was the discovery of Ramanujan. He called their collaboration "the one romantic incident in my life."
Hardy preferred his work to be considered pure mathematics, perhaps because of his detestation of war and the military uses to which mathematics had been applied. He made several statements similar to that in his Apology:
"I have never done anything 'useful'. No discovery of mine has made, or is likely to make, directly or indirectly, for good or ill, the least difference to the amenity of the world."

However, aside from formulating the Hardy–Weinberg principle in population genetics, his famous work on integer partitions with his collaborator Ramanujan, known as the Hardy–Ramanujan asymptotic formula, has been widely applied in physics to find quantum partition functions of atomic nuclei (first used by Niels Bohr) and to derive thermodynamic functions of non-interacting Bose-Einstein systems. Though Hardy wanted his maths to be "pure" and devoid of any application, much of his work has found applications in other branches of science.*Wik
Hardy was afraid of flying throughout his life, and saw God as his great enemy.  This combination of quirks led to a strange story about a rushed flight to France. He informed his housekeeper that he had left an important note on his desk.The note was opened and read, "I have discovered a simple proof of Fermat's Last theorem.  Details on my return!"
His excited colleagues mobbed him on his return pressing for details of the proof.  
"Oh, That," he laughed.  "That was just insurance. I just thought God would not let me die and receive undue credit for such a major proof." *PBnotes

Wendy Appleby commented:
Hardy joined the Royal Astronomical Society so that he could attend its meetings and listen to Sir Arthur Eddington arguing with Sir James Jeans.  He was a keen follower of cricket.  He described the greatest mathematicians as being in the "Hobbs class", referring to Sir Jack Hobbs, who still holds the world record for the most runs and the most centuries scored in first-class matches.  Later he amended that to the "Bradman class", arguing that Sir Donald Bradman was even better than Hobbs.





1883 Eric Temple Bell (7 Feb 1883; 21 Dec 1960 at age 77) Scottish-American mathematician and writer who contributed to analytic number theory (in which he found several important theorems), Diophantine analysis and numerical functions. In addition to about 250 papers on mathematical research, he also wrote for the layman in Men of Mathematics (1937) and Mathematics, Queen and Servant of Science (1951) among others. Under the name of John Taine, he also wrote science fiction. *TIS Although he was a well known mathematician in his day, he is best remembered for his popular Men of Mathematics. This book is hated by historians of mathematics for its exaggerations and inaccuracies, but it is loved by high school students, and has motivated many mathematicians to become mathematicians. If you have not read it, do! *VFR



1897 Maxwell Herman Alexander "Max" Newman, FRS (7 February 1897 – 22 February 1984) was a British mathematician and codebreaker. After WWII he continued to do research on combinatorial topology during a period when England was a major center of activity, notably Cambridge under the leadership of Christopher Zeeman. Newman made important contributions leading to an invitation to present his work at the 1962 International Congress of Mathematicians in Stockholm at the age of 65, and proved a Generalized Poincaré conjecture for topological manifolds in 1966. He died in Cambridge.*Wik




1898 Charles Wilderman Trigg,(Feb 7, 1898 Baltimore, Md; June 28, 1989 San Diego, Ca.) American engineer, mathematician and educator. Educated in engineering, mathematics and education at University of Pittsburgh, University of Southern California and University of California at Los Angeles. Worked as an industrial chemist and engineer, 1917-1943, and as an educator and administrator, 1946-1963. Served in the United States Navy during World War II. Book review editor of the Journal of Recreational Mathematics. Considered one of the foremost recreational mathematicians of the twentieth century. *U of Calgary Archives



1899 Hans Jenny (7 Feb 1899; 9 Jan 1992 at age 92) Swiss agricultural chemist and pedologist (soil scientist) who developed numerical functions to describe soil in terms of five interacting factors in his book Factors of Soil Formation (1941). These related Climate (temperature and moisture); Organisms (those living on the soil and in the soil, vegetation and animals, fungi algae and bacteria, decay of organic matter, humus); Relief (topography, and geomorphic landscape); Parent Material (bedrock or sediment type); and Time (ranging from 100's to 1000's of years while maturity or equilibrium of soil development is attained). He moved to the U.S. in 1926. After retirement, he studied the soil relationships in the unusual ecological community of the Pygmy Forest in California, known for its stunted and twisted confers. *TIS




1905 Lucien Alexandre Charles René de Possel (Feb 7, 1905– ?, 1974) was a French mathematician, one of the founders of the Bourbaki group, and later a pioneer computer scientist, working in particular on optical character recognition.
He had the conventional background for a member of Bourbaki: the École Normale Supérieure, agrégation, and then study in Germany. He left Bourbaki at an early stage: there was an obvious personal matter intruding between him and André Weil who had married De Possel's ex-wife Eveline following her divorce from De Possel in 1937.
De Possel published an early book on game theory in 1936 (Sur la théorie mathématique des jeux de hasard et de réflexion). His later research work in computer science at the Institut Blaise Pascal was in a position of relative isolation, as the subject strove for independence and to move away from the imposed role of service provider in the field of numerical analysis. *Wik
First Bourbaki Conference 1935
(L to R) Mandelbrojt, Chevalley, de Possel, Weil



1909 Kōsaku Yosida ( 7 February 1909, Hiroshima – 20 June 1990) was a Japanese mathematician who worked in the field of functional analysis. He is known for the Hille-Yosida theorem concerning C0-semigroups. Yosida studied mathematics at the University of Tokyo, and held posts at Osaka and Nagoya Universities. In 1955, Yosida returned to the University of Tokyo. *Wik

In 1933 Yosida was appointed as an Assistant in the Department of Mathematics at Osaka Imperial University. Osaka is on Honshu Island, roughly half way between Hiroshima and Tokyo. The Osaka Imperial University is based on educational institutions dating back to the 18th century but only became a university in 1931, two years before Yosida was appointed there. After one year, he was promoted to Associate Professor.

Moving to Osaka Imperial University led to Yosida changing the direction of his research. Two mathematicians who joined the Department of Mathematics shortly after him and were to strongly influence him were Mitio Nagumo (1905-1995) and Shizuo Kakutani. Nagumo had graduated from Tokyo Imperial University in March 1928 and spent two years at the University of Göttingen, Germany, before being appointed to Osaka Imperial University in March 1934. Kakutani had studied at Tohoku University in Sendai before being appointed as a teaching assistant at Osaka Imperial University in 1934. Yosida became interested in functional analysis through discussions with these two mathematicians. He published several joint papers with Kakutani. *SAU





DEATHS


1736 Stephen Gray (December 1666 – 7 February 1736) was an English dyer and amateur astronomer, who was the first to systematically experiment with electrical conduction, rather than simple generation of static charges and investigations of the static phenomena.
Gray was born in Canterbury, Kent and after some basic schooling, he was apprenticed to his father (and later his elder brother) in the cloth-dyeing trade. His interests lay with natural science and particularly with astronomy, and he managed to educate himself in these developing disciplines, mainly through wealthy friends in the district who gave him access to their libraries and scientific instruments.
Stephen Gray produced a long series of experiments with electricity. In producing charge on a long glass tube, he discovered in 1729 that he could communicate the electrical effect to other objects by direct connection. Using string, he could charge an object over 50 feet from the rubbed tube, but oddly enough some other substances, such as silk thread, would not carry charge. Brass wire would transmit charge even better. These experiments with charged strings and glass tubes revealed the properties of conduction, insulation, and transmission. From these experiments came an understanding of the role played by conductors and insulators (names applied by John Desaguliers).
Despite the importance of his discoveries (it can be argued that he was the inventor of electrical communications) he received little credit at the time because of the factional dispute in the Royal Society, and the dominance of Newtonianism (which became the Masonic 'ideology'). By the time his discoveries were publicly recognised, experiments in electricity had moved rapidly on and his past discoveries tended to look trivial. For this reason, some historians tend to overlook his work.

There is no monument to Gray, and little recognition of what he achieved, against all odds, in his scientific discoveries. He is believed to be buried in a common grave in an old London cemetery, in an area reserved for pauper pensioners from the Charterhouse. *Wik *Yovisto
In a famous experiment Stephen Gray demonstrated static electricity
by charging a boy suspended by insulating strings in 1744 *Yovisto

1897 Galileo Ferraris (31 Oct 1847 - 7 Feb 1897 at age 49) Italian physicist who studied optics, acoustics and several fields of electrotechnics, but his most important discovery was the rotating magnetic field. He produced the field with two electromagnets in perpendicular planes, and each supplied with a current that was 90º out of phase. This could induce a current in a incorporated copper rotor, producing a motor powered by alternating current. He produced his first induction motor (with 4 poles) in May-Jun 1885. Its principles are now applied in the majority of today's a.c. motors, yet he refused to patent his invention, and preferred to place it at the service of everyone. *TIS



1809 James Glaisher FRS (7 April 1809 – 7 February 1903) was an English meteorologist, aeronaut and astronomer.

Born in Rotherhithe, the son of a London watchmaker, Glaisher was a junior assistant at the Cambridge Observatory from 1833 to 1835[2] before moving to the Royal Observatory, Greenwich, where he served as Superintendent of the Department of Meteorology and Magnetism at Greenwich for 34 years.

In 1845, Glaisher published his dew point tables for the measurement of humidity. He was elected a Fellow of the Royal Society in June 1849.

He was a founding member of the Meteorological Society (1850) and the Aeronautical Society of Great Britain (1866). He was president of the Royal Meteorological Society from 1867 to 1868. Glaisher was elected a member of The Photographic Society, later the Royal Photographic Society, in 1854 and served as the society's president for 1869–1874 and 1875–1892.[6] He remained a member until his death. He was also President of the Royal Microscopical Society. He is most famous as a pioneering balloonist. Between 1862 and 1866, usually with Henry Tracey Coxwell as his co-pilot, Glaisher made numerous ascents to measure the temperature and humidity of the atmosphere at the greatest altitudes attainable at that time.

Their ascent on 5 September 1862 broke the world record for altitude but he passed out around 8,800 metres (28,900 feet) before a reading could be taken. One of the pigeons making the trip with him died. Estimates suggest that he rose to more than 9,500 metres (31,200 feet) and as much as 10,900 metres (35,800 feet) above sea level. Glaisher lost consciousness during the ascent and Coxwell lost all sensation in his hands. The valve-line had become entangled so he was unable to release the mechanism; with great effort, he climbed onto the rigging and was finally able to release the vent before losing consciousness. This allowed the balloon to descend to a lower altitude.

The two made additional flights. According to the Smithsonian Institution, Glaisher "brought along delicate instruments to measure the temperature, barometric pressure and chemical composition of the air. He even recorded his own pulse at various altitudes".

In 1871, Glaisher arranged for the publication of his book about the balloon flights, Travels in the Air, a collection of reports from his experiments. To ensure that numerous members of the general public would learn from his experiences, he included "detailed drawings and maps, colorful accounts of his adventures and vivid descriptions of his precise observations", according to one report.  

He died in Croydon, Surrey in 1903, aged 93. *Wik

James Glaisher (left) and Henry Tracey Coxwell Ballooning in 1864




1948 Poul Heegaard (2 Nov 1871 in Copenhagen, Denmark - 7 Feb 1948 in Oslo, Norway) was a Danish mathematician who (with Max Dehn) was the first to classify compact surfaces.*SAU His 1898 thesis introduced a concept now called the Heegaard splitting of a 3-manifold. Heegaard's ideas allowed him to make a careful critique of work of Henri Poincaré. Poincaré had overlooked the possibility of the appearance of torsion in the homology groups of a space.
He later co-authored, with Max Dehn, a foundational article on combinatorial topology, in the form of an encyclopedia entry.
Heegaard studied mathematics at the University of Copenhagen, from 1889 to 1893 and following years of traveling, and teaching mathematics, he was appointed professor at University of Copenhagen in 1910.
Following a dispute with the faculty over, among other things, the hiring of Harald Bohr (The Brother of Niels Bohr, and Olmpic Soccer medalist) as professor at the University (Heegaard was against it); Heegaard accepted a professorship at Oslo in Norway, where he worked till his retirement in 1941.*Wik




1969 Hans Rademacher (3 April 1892 in Wandsbeck (part of Hamburg), Schleswig-Holstein, Germany - 7 Feb 1969 in Haverford, Pennsylvania, USA) It was philosophy that he intended to take as his main university subject when he entered the university of Göttingen in 1911, but he was persuaded to study mathematics by Courant after having enjoyed the excellent mathematics teaching of Hecke and Weyl. He is remembered for the system of orthogonal functions (now known as Rademacher functions) which he introduced in a paper published in 1922. Berndt writes "Since its discovery, Rademacher's orthonormal system has been utilised in many instances in several areas of analysis." Rademacher's early arithmetical work dealt with applications of Brun's sieve method and with the Goldbach problem in algebraic number fields. About 1928 he began research on the topics for which he is best known among mathematicians today, namely his work in connection with questions concerning modular forms and analytic number theory. Perhaps his most famous result, obtained in 1936 when he was in the United States, is his proof of the asymptotic formula for the growth of the partition function (the number of representations of a number as a sum of natural numbers). This answered questions of Leibniz and Euler and followed results obtained by Hardy and Ramanujan. Rademacher also wrote important papers on Dedekind sums and investigated many problems relating to algebraic number fields. *SAU




Credits :
*CHM=Computer History Museum
*FFF=Kane, Famous First Facts
*NSEC= NASA Solar Eclipse Calendar
*RMAT= The Renaissance Mathematicus, Thony Christie
*SAU=St Andrews Univ. Math History
*TIA = Today in Astronomy
*TIS= Today in Science History
*VFR = V Frederick Rickey, USMA
*Wik = Wikipedia
*WM = Women of Mathematics, Grinstein & Campbell

Friday, 6 February 2026

Before there were Four-Fours, there were four threes, and several others

 

*Eyegate Gallery



EVERYONE has encountered the four-fours problem, using four fours and whatever mathematical operations that were allowed to make a number, or a set of numbers. You may even have read that it originated in the famous book of recreations by W. W. Rouse Ball; Wikipedia still has, "The first printed occurrence of this activity is in 'Mathematical Recreations and Essays' by W. W. Rouse Ball published in 1892. In this book it is described as a 'traditional recreation'. "

I know you've heard it before, but here we go again, "Wikipedia is wrong about that."

The first record I have found of a puzzle like these was in an 1818 edition of The schoolmaster's assistant: being a compendium of arithmetic both practical and theoretical : in five parts, and early American Arithmetic by Thomas Dilworth.

This image is from page 189 and part of a collection of "Short and Diverting Questions". As is typical of many of the early such problems, there were no specifications for the operations that might be employed. I have found the same exact problem in the 1800 edition.
In the same collection of problems, Dilworth poses a problem requesting the use of four threes...(which should give you a big clue if you are stuck on the previous problem of using four figures to make 12.

Ok, even I can do that one, and the dd+d/d format becomes a regular problem through the years with different digits; the most common being in the form of "use four nines to make 100."

Professor Singmaster says that both the Dilworth problems appear in a 1743 edition of this book.
By 1788 similar problems show up in another classic American Arithmetic by Nicolas Pike,"Said Harry to Edmund, I can place four 1's so that, when added, they shall make precisely 12. Can you do so too?"

The first printed version I can find of a question like this that asks about using three or four of the same number to find a set of integers appears in 1881 in a U.K. magazine called, Knowledge: an Illustrated Magazine of Science. It was founded and edited by Richard A Proctor, the English astronomer who is remembered for his maps of Mars (and has a crater there named for him). It may be that the Cupidus Scientiae who submitted the question is, in fact, the editor.


The next edition (Jan 6, 1882) did indeed carry the solutions, as well as correspondence from an H. Snell who provides that 19 = 4! - 4 - 4/4 (I have used the conventional current symbol for factorial but Snell used the Jarret symbol for factorial which looks like a right angle symbol with the number on the horizontal line and was popular at that time.)
The editor felt that factorials were inappropriate for the problem as posed. The following week (Jan 13,1882) there were several solutions for 19 from contributors, including (4+4-.4)/.4.

When W. W. Rouse Ball got into the act, it was in the third edition of his MRE 1896 and it was a long step away from the four-fours as we have come to know it. He repeated a problem previously used by Sam Loyd in 1893 which became popular in the United Kingdom; "Make 82 with the seven digits 9, 8, 7, 6, 5, 4, 0." Loyd offered a prize of 100 pounds for the solution. The solution, involving the use of repeating fractions, was given as 80.5 + .97 + .46 = 82 with all the decimal values repeating. This was indicated in the period by using a single dot above the values which repeated.

It was not until the fifth edition of 1911 of MRE that Ball gives the more common version, and describes it as, "An arithmetical amusement, said to have been first propounded in 1881,...) which seems to refer to the posting in Knowledge. By the sixth edition (1914) he has extended the problem to four nines and four threes. This one is significant because it seems to be the first that discusses what values can be achieved by what set of operations.

After a while it even caught on with higher level mathematicians. In 1991 Clifford A. Pickover asked for good approximations to Phi, (oft called the golden mean or golden ratio)  using four fours.

\( \Phi = \frac{\sqrt(4) + \sqrt (4! - 4)}{4} = \frac{1 + \sqrt(5)}{2}\)


A problem on Stack Exchange asked for four-fours to make pi.  Maybe send your best response to these and your other favorite math constants.  I'll keep updating with the good ones. (The really great ones I'll act like I thought of them first,) Use any operations that are commonly known.  

Here is a short approach,  π=arccos((4−4)− (4/4)) = Arccos (-1) .... because cos(π)=  -1

In 1999 it became popular to ask for integers created using the digits 1, 9, 9, 9.
And it seems I saw a few of those floating around the internet at the beginning of 2012.

maybe you can rake a shot using 2,0,2,3 and see how many you can get with your choice of operations.  I can get 21 and 25 quickly, the rest are up to you folks.

But remember, it all started with Jack and Harry, and four-threes.

On This Day in Math - February 6

  

Newton Statue - Trinity Chapel, Cambridge UK

The feeling of it (pure oxygen) to my lungs was not sensibly different from that of common air; but I fancied that my breast felt peculiarly light and easy for some time afterwards. Who can tell but that, in time, this pure air may become a fashionable article in luxury. Hitherto only two mice and myself have had the privilege of breathing it.~Joseph Priestley

The 37th day of the year; 37 is the only prime with a three digit period for the decimal expansion of its reciprocal, 1/37 = .027027....  But 37 has a strange affinity with 27, which also has a three digit period for its reciprocal, .037037...,   The affinity, of course, is due to 27 x 37 = 999


Big Prime:::   n = integer whose digits are (left to right) 6424 copies of 37, followed by units digit of 3, is prime (n = 3737...373 has 12849 digits) *Republic of Math ‏@republicofmath

An amazing reversal: 37 is the 12th prime & 73 is the 21st prime . This enigma is the only known combination.

If you use multiplication and division operations to combine Fibonacci numbers, (for example, 4 = 2^2, 6 = 2·3, 7 = 21/ 3 ,...) you can make almost any other number. Almost, but you can't make 37.  In fact, there are 12 numbers less than 100 that can not be expressed as "Fibonacci Integers" *Carl Pomerance, et al.

Any number divisible by 37 will still be divisible by 37 if you rotate its digits, 148, 481, 1nd 814 are all divisible by 37.  
 
EVENTS
1672 Newton wrote Henry Oldenburg about his optical theories, (including the phrase, "because that Light is a heterogenous mixture of differently refrangible rays." and Oldenburg published them a few days later in the
Philosophical Transactions. The controversy that followed dissuaded Newton from publishing on optics—and also on the calculus—until 1704 *ISIS, 69, p 134 (*VFR)
But it is requisite, that the prism and lens be placed steady, and that the paper, on which the colours are cast be moved to and fro; for, by such motion, you will not only find, at what distance the whiteness is most perfect but also see, how the colours gradually convene, and vanish into whiteness, and afterwards having crossed one another in that place where they compound whiteness, are again dissipated and severed, and in an inverted order retain the same colours, which they had before they entered the composition. You may also see, that, if any of the colours at the lens be intercepted, the whiteness will be changed into the other colours. And therefore, that the composition of whiteness be perfect, care must be taken, that none of the colours fall besides the lens.
Some of his opponents denied the truth of his experiments, refusing to believe in the existence of the spectrum. Others criticized the experiments, saying that the length of the spectrum was never more than three and a half times the breadth, whereas Newton found it to be five times the breadth. It appears that Newton made the mistake of supposing that all prisms would give a spectrum of exactly the same length;

1766 Just a few months before he returns to St. Petersburg, Euler reads his paper (E401) “A New Method for Comparing the Observation of the Moon to Theory” to the Berlin Academy. The paper proposes numerical techniques for approximating a body's velocity and acceleration. Sandifer suggests that the paper had great influence on LaGrange’s foundational program for the Calculus. *Ed Sandifer, How Euler Did It, MAA

1828 George Biddell Airy appointed Plumian professor of astronomy at Cambridge at a salary of £500 per annum. He was appointed even after he raised a row that the previous salary of £300 was inadequate. For the previous two years he held the Lucasian professorship—the post Newton held—at a salary of £99. *VFR




1930 Kurt G¨odel received his Ph.D. from the University of Vienna for a dissertation, directed by Hans Hahn, that showed the completeness of first order logic (every valid first-order formula is provable). *VFR

Gödel's discoveries in the foundations of mathematics led to the proof of his completeness theorem in 1929 as part of his dissertation to earn a doctorate at the University of Vienna, and the publication of Gödel's incompleteness theorems two years later, in 1931. The incompleteness theorems address limitations of formal axiomatic systems. In particular, they imply that a formal axiomatic system satisfying certain technical conditions cannot decide the truth value of all statements about the natural numbers, and cannot prove that it is itself consistent.[4][5] To prove this, Gödel developed a technique now known as Gödel numbering, which codes formal expressions as natural numbers.

Gödel also showed that neither the axiom of choice nor the continuum hypothesis can be disproved from the accepted Zermelo–Fraenkel set theory, assuming that its axioms are consistent. The former result opened the door for mathematicians to assume the axiom of choice in their proofs. He also made important contributions to proof theory by clarifying the connections between classical logic, intuitionistic logic, and modal logic.






1935,
 the board game Monopoly went on sale under its present day name for the first time.  Prior to being purchased by Parker Brothers, the game had been developed by Elizabeth Magie under the name, “The Landlord’s Game.”  Magie intended the game to give an economic lesson about land value tax. Parker Brothers initially rejected the game, claiming that it was too complicated and took too long to finish, but later changed their opinion based on the game’s popularity in Pennsylvania.

Monopoly has grown into one of Parker Brothers’ most successful board game franchises. 
*Famous Daily





1959 Kilby Files Patent For Integrated Circuit.
Jack Kilby of Texas Instruments files a patent application called "miniaturized electronic circuits" for his work on a multi-transistor device. The patent was only one of 60 that Kilby holds. While Kilby has the earliest patent on the "integrated circuit," it was Robert Noyce, later co-founder of Intel, whose parallel work resulted in a practical device. Kilby's device had several transistors connected by flying wires while Noyce devised the idea of interconnection via a layer of metal conductors. Noyce also adapted Jean Hoerni's planar technique for making transistors to the manufacture of more complex circuits. *CHM
Two drawings from Kilby's first IC patent *haverford.edu



BIRTHS

1465 Scipione del Ferro (6 February 1465 – 5 November 1526) born in Bologna, Italy. Around 1515 he solved the cubic equations x3+px = q and x3= px + q when p and q are positive. His methods are unknown. This information was passed on to his son-in-law Annibale dalla Nave who was tricked into revealing it to Cardano, who published it in his Ars magna of 1545.*VFR
There are no surviving scripts from del Ferro. This is in large part due to his resistance to communicating his works. Instead of publishing his ideas, he would only show them to a small, select group of friends and students. It is suspected that this is due to the practice of mathematicians at the time of publicly challenging one another. When a mathematician accepted another's challenge, each mathematician needed to solve the other's problems. The loser in a challenge often lost funding or his university position. Del Ferro was fearful of being challenged and likely kept his greatest work secret so that he could use it to defend himself in the event of a challenge.
Despite this secrecy, he had a notebook where he recorded all his important discoveries. After his death in 1526, this notebook was inherited by his son-in-law Hannival Nave, who was married to del Ferro's daughter, Filippa. Nave was also a mathematician and a former student of del Ferro's, and he replaced del Ferro at the University of Bologna after his death. In 1543, Gerolamo Cardano and Lodovico Ferrari (one of Cardano's students) travelled to Bologna to meet Nave and learn about his late father-in-law's notebook, where the solution to the depressed cubic equation appeared.
Del Ferro also made other important contributions to the rationalization of fractions with denominators containing sums of cube roots.
He also investigated geometry problems with a compass set at a fixed angle, but little is known about his work in this area. *Wik (Teachers may need to explain to students how suppression of the squared term allows this to solve general cubics.)
Four years before del Ferro died, the brilliant mind that would solve the quartic (fourth power) equation was born.  His name was  Lodovico Ferrari.





1695 Nicolaus II Bernoulli (February 6, 1695, Basel, Switzerland – July 31, 1726, St. Petersburg, Russia) was a Swiss mathematician and was one of the many prominent mathematicians in the Bernoulli family. Nicolaus worked mostly on curves, differential equations, and probability. He was a contemporary of Leonhard Euler. He also contributed to fluid dynamics.*Wik He was the oldest and favorite of three sons of Johann Bernoulli. He made important mathematical contributions to the problem of trajectories while working on the mathematical arguments behind the dispute between Newton and Leibniz.*SAU When the father was asked to come to St. Petersburg to join the Academy, he declined because of his age. He suggested that they take his son Nikolaus, but, so that he not be lonely, they should also take another son Daniel. Unfortunately, Nikolaus II drowned in 1726, only eight months after going to St. Petersburg. His professorship was succeeded in 1727 by Leonhard Euler, whom the Bernoulli brothers had recommended.




1802 Sir Charles Wheatstone, (6 Feb 1802, 19 Oct 1875) English physicist who popularized the Wheatstone bridge, a device that accurately measured electrical resistance and became widely used in laboratories. He didn't actually invent the "Wheatstone Bridge". His contemporary, Samuel Hunter Christie, came up with the idea of the bridge circuit, but Wheatstone set the precedent for using it in the way in which it has been most commonly used. Over time, the device became associated with him and took on his name. He did, however, invent the concertina (1829), the stereoscope (1838), and an early form of the telegraph. He also developed a chronoscope (1842) to determine the velocity of projectiles at an English gunnery.*TIS (For students of discrete math, or interested in codes, Wheatstone was also the creator of the Playfair Cipher.) {Wheatstone's work was so diverse that after a lecture at the Science Conference in South Kensington (London) by Prof. W. G. Adams on Wheatstone's acoustical discoveries, William Spottiswoode commented, "It must have struck all those in science... that when they fancied they had found something new, they find it was done by Sir Charles Wheatstone years ago." *Knowledge and Scientific News, Jan 1908, pg 7




1824 William Huggins (7 February 1824 – 12 May 1910) was an English amateur astronomer. He built his own private observatory, called Tulse Hill, in London in 1856, and when spectroscopy was established as a scientific field of inquiry in 1859, Huggins jumped at the chance to apply it to astronomy. He said he felt like a parched man spying water in the desert. In the early 1860s, he examined the light of several nebulae and found that the spectral lines were those of a gas, not stars , and suggested that at least some nebulae were gaseous in nature (at the time, no one knew what nebulae were, except that they were nebulous).

In 1868, Huggins discovered that the spectral lines of the star Sirius are shifted slightly to the red end of the spectrum, which he recognized as a indication that Sirius is moving away from us, and he even measured its speed of recession. Huggins's wife was his close collaborator throughout his career, and just before he died, he and Lady Huggins republished all his scientific papers in a beautiful volume, The Scientific Papers of Sir William Huggins (1909) *Linda Hall Org




1875  Joseph Winlock (February 6, 1826 – June 11, 1875) was an American astronomer and mathematician.

He was born in Shelby County, Kentucky, the grandson of General Joseph Winlock (1758–1831). After graduating from Shelby College in Kentucky in 1845, he was appointed professor of mathematics and astronomy at that institution.

From 1852 until 1857 he worked as a computer for the American Ephemeris and Nautical Almanac, and relocated to Cambridge, Massachusetts. He briefly served as head of the department of mathematics at the United States Naval Academy, but returned as superintendent of the Almanac office. He was elected a Fellow of the American Academy of Arts and Sciences in 1853.

He married Isabella Washington in Shelbyville, Kentucky on December 10, 1856, and they had six children.

In 1863 he was one of the fifty charter members of the National Academy of Sciences.[4] Three year later in 1866 he became director of the Harvard College Observatory, succeeding George Bond, and making many improvements in the facility. He was also appointed professor of astronomy at Harvard. He remained at the university, eventually becoming professor of geodesy until his sudden death in Cambridge on June 11, 1875.

Much of his astronomical work included measurements with the meridian circle, a catalogue of double stars and stellar photometry investigations. He also led solar eclipse expeditions to Kentucky in 1860 and Spain in 1870.

The crater Winlock on the Moon is named after him.



1848 Adam Wilhelm Siegmund Günther (6 Feb 1848 in Nuremberg, Germany - 3 Feb 1923 in Munich, Germany) Günther's contributions to mathematics include a treatise on the theory of determinants (1875), hyperbolic functions (1881), and the parabolic logarithm and parabolic trigonometry (1882). He also wrote numerous books and journal articles [which] encompass both pure mathematics and its history and physics physics, geophysics, meteorology, geography, and astronomy. The individual works on the history of science, worth reading even today, bear witness to a thorough study, a remarkable knowledge of the relevant secondary literature, and a superior descriptive ability. *SAU



1900 Rosalind Cecilia Hildegard Tanner (née Young) (5 February 1900 – 24 November 1992) was a mathematician and historian of mathematics. She was the eldest daughter of the mathematicians Grace and William Young. She was born and lived in Göttingen in Germany (where her parents worked at the university) until 1908. During her life she used the name Cecily.

Cecily joined the University of Lausanne in 1917. She also helped her father's research between 1919 and 1921 at the University College Wales in Aberystwyth, and worked with Edward Collingwood, also of Aberystwyth, on a translation of Georges Valiron's course on Integral Functions. She received a L-És-sc (a bachelor's degree) from Lausanne in 1925.

She then studied at Girton College, Cambridge, gaining a PhD in 1929 under the supervision of Professor E. W. Hobson for research on Stieltjes integration. She accepted a teaching post at Imperial College, London where she worked until 1967.

After 1936, most of her research was in the history of mathematics, and she had a particular interest in Thomas Harriot, an Elizabethan mathematician. She set up the Harriot Seminars in Oxford and Durham. Rosalind married William Tanner in 1953; however, he died a few months after their marriage.

In 1972 she and Ivor Grattan-Guinness published a second edition of her parents' book The Theory of Sets of Points, originally published in 1906.
Mrs. R. C. H. Young (left, upper) at the ICM 1932



1916 John Crank (6 February 1916 – 3 October 2006) was a mathematical physicist, best known for his work on the numerical solution of partial differential equations.
He worked on ballistics during the Second World War, and was then a mathematical physicist at Courtaulds Fundamental Research Laboratory from 1945 to 1957. In 1957, he was appointed as the first Head of Department of Mathematics at Brunel College in Acton. He served two terms of office as Vice-Principal of Brunel before his retirement in 1981, when he was granted the title of Professor Emeritus.
Crank's main work was on the numerical solution of partial differential equations and, in particular, the solution of heat-conduction problems. He is best known for his work with Phyllis Nicolson on the heat equation, which resulted in the Crank–Nicolson method.*Wik




DEATHS

1612 Christopher Clavius (March 25, 1538 – February 6, 1612 {some sources give Feb 12 for the date of death}), the Euclid of the sixteenth-century, born in the German town of Bamberg, the see of the prince-bishop of Franconia. He was also the leader of the Gregorian calendar reform. Perhaps his greatest contribution was as an educational reformer. *Renaissance Mathematicus He was a German Jesuit mathematician and astronomer who was the main architect of the modern Gregorian calendar. In his last years he was probably the most respected astronomer in Europe and his textbooks were used for astronomical education for over fifty years in Europe and even in more remote lands (on account of being used by missionaries). As an astronomer Clavius held strictly to the geocentric model of the solar system, in which all the heavens rotate about the Earth. Though he opposed the heliocentric model of Copernicus, he recognized problems with the orthodox model. He was treated with great respect by Galileo, who visited him in 1611 and discussed the new observations being made with the telescope; Clavius had by that time accepted the new discoveries as genuine, though he retained doubts about the reality of the mountains on the Moon. Later, a large crater on the Moon was named in his honour. *Wik



Stephen Gray (December 1666 – 7 February 1736) was an English dyer and astronomer who was the first to systematically experiment with electrical conduction. Until his work in 1729 the emphasis had been on the simple generation of static charges and investigations of the static phenomena (electric shocks, plasma glows, etc.). Gray showed that electricity can be conducted through metals and that it appeared on the surfaces of insulators.
Gray went on to make more electrical discoveries, the most noticeable being electrical induction (creating an electrical charge in a suspended object without contact). In 1729 Gray showed that the "Electrik Vertue" of a glass tube can be conducted via a metal to another body. This was the first evidence that electricity was not a property of the glass tube but some kind of fluid. That same year Gray create two oaken cubes, one solid and one hollow; observing that these had the same electrical properties demonstrated that electricity was a surface rather than a bulk character.

This experiment was widely celebrated around Europe as the famous "Flying Boy" demonstration: a boy was suspended on silk cords, and then charged by Gray bringing his rubbed tube (static electric generator) close to the boy's feet, but without touching. Gray showed that the boy's face and hands still attracted the chaff, paper and other materials. Gray noted the crackling of 'electric virtue' resembled lightning (as did other experimenters), foreshadowing the great discoveries of Benjamin Franklin nearly a century later.
Stephan Gray's “electric boy” experiment, in which a boy hanging from insulating silk ropes is given an electric charge. A group are gathered around. A woman is encouraged to bend forward and poke the boy's nose, to get an electric shock.*Wik






1804 Joseph Priestley (13 Mar 1733, 6 Feb 1804) English chemist, clergyman and political theorist who discovered the element oxygen. His early scientific interest was electricity, but he is remembered for his later work in chemistry, especially gases. He investigated the "fixed air" (carbon dioxide) found in a layer above the liquid in beer brewery fermentation vats. Although known by different names at the time, he also discovered sulphur dioxide, ammonia, nitrogen oxides, carbon monoxide and silicon fluoride. Priestley is remembered for his invention of a way of making soda-water (1772), the pneumatic trough, and recognizing that green plants in light released oxygen. His political opinions and support of the French Revolution, were unpopular. After his home and laboratory were set afire (1791), he sailed for America, arriving at New York on 4 Jun 1794 *TIS He died on the morning of 6 February 1804 and was buried at Riverview Cemetery in Northumberland, Pennsylvania.

Priestley's epitaph reads:
Return unto thy rest, O my soul, for the
Lord hath dealt bountifully with thee.
I will lay me down in peace and sleep till
I awake in the morning of the resurrection. *Wik

*cometography.com
1923 Edward Emerson Barnard (16 Dec 1857; 6 Feb 1923) astronomer who pioneered in celestial photography, specializing in wide-field photography. From the time he began observing in 1881, his skill and keen eyesight combined to make him one of the greatest observers. Barnard came to prominence as an astronomer through the discovery of numerous comets. In the 1880s, a patron of astronomy in Rochester, N.Y. awarded $200 per new comet was found. Barnard discovered eight - enough to build a "comet house" for his bride. At Lick Observatory (1888-95) he made the first photographic discovery of a comet; photographed the Milky Way; and discovered the fifth moon of Jupiter. Then he joined Yerkes Observatory, making his Photographic Atlas of Selected Regions of the Milky Way.*TIS The faint Barnard's Star is named for Edward Barnard after he discovered in 1916 that it had a very large proper motion, relative to other stars. This is the second nearest star system to the Sun, second only to the Alpha Centauri system. *Wik


1965 Ernst Erich Jacobsthal (16 October 1882, Berlin – 6 February 1965, Überlingen) was a German mathematician, and brother to the archaeologist Paul Jacobsthal.
In 1906, he earned his PhD at the University of Berlin, where he was a student of Georg Frobenius, Hermann Schwarz and Issai Schur; his dissertation, Anwendung einer Formel aus der Theorie der quadratischen Reste (Application of a Formula from the Theory of Quadratic Remainders), provided a proof that prime numbers of the form 4n + 1 are the sum of two square numbers. *Wik The theory was first conjectured by Fermat and proved by Euler.




1973 Ira Sprague Bowen (21 Dec 1898; 6 Feb 1973) was an American astrophysicist. His investigation of the ultraviolet spectra of highly ionized atoms led to his explanation of the unidentified strong green spectral lines of gaseous nebulae (clouds of rarefied gas) as forbidden lines of ionized oxygen and nitrogen. This emission, appearing to match no known element, had formerly been suggested to be due to a hypothetical element, "nebulium." Bowen was able to show, that in reality, the emission lines exactly matched those calculated to be the "forbidden lines" of ionized oxygen and nitrogen under extremely low pressure. This made a major advance in the knowledge of celestial composition. He was director of the Mt. Wilson and Palomar Observatories from 1948-64.*TIS
Ira Bowen (right) in the lab with Robert Millikan.



1992 Caius Jacob (29 March 1912 , Arad - 6 February 1992 , Bucharest ) was a Romanian mathematician and member of the Romanian Academy. He made ​​contributions in the fields of fluid mechanics and mathematical analysis , in particular vigilance in plane movements of incompressible fluids, speeds of movement at subsonic and supersonic , approximate solutions in gas dynamics and the old problem of potential theory. His most important publishing was Mathematical introduction to the mechanics of fluids. *Wik



2017 Raymond Merrill Smullyan ( May 25, 1919 -February 6, 2017) is an American mathematician, concert pianist, logician, Taoist philosopher, and magician. His first career (like Persi Diaconis a generation later) was stage magic. He then earned a BSc from the University of Chicago in 1955 and his Ph.D. from Princeton University in 1959. He is one of many logicians to have studied under Alonzo Church. Smullyan is the author of many books on recreational mathematics, recreational logic, etc. Most notably, one is titled "What Is the Name of This Book?". *Wik For example the book is described on the cover as follows:"Beginning with fun-filled monkey tricks and classic brain-teasers with devilish new twists, Professor Smullyan spins a logical labyrinth of even more complex and challenging problems as he delves into some of the deepest paradoxes of logic and set theory, including Gödel's revolutionary theorem of undecidability."
Martin Gardner described this book in Scientific American as:"The most original, most profound and most humorous collection of recreational logic and mathematics problems ever written."







Credits :
*CHM=Computer History Museum
*FFF=Kane, Famous First Facts
*NSEC= NASA Solar Eclipse Calendar
*RMAT= The Renaissance Mathematicus, Thony Christie
*SAU=St Andrews Univ. Math History
*TIA = Today in Astronomy
*TIS= Today in Science History
*VFR = V Frederick Rickey, USMA
*Wik = Wikipedia
*WM = Women of Mathematics, Grinstein & Campbell