Jean François Théophile Pépin (14 May 1826 – 3 April 1904) was a French mathematician. Born in

Cluses Cluses (; ) is a commune in the Haute-Savoie department in the Auvergne-Rhône-Alpes region in southeastern France. Citizens are known as ''Clusiens''. The commune is situated in the Arve Valley, on the river which bears the same name. Cluse ...

Haute-Savoie Haute-Savoie () is a Departments of France, department in the Auvergne-Rhône-Alpes Regions of France, region of Southeastern France, bordering both Switzerland and Italy. Its Prefectures in France, prefecture is Annecy. To the north is Lake Gene ...

, he became a

Jesuit The Society of Jesus (; abbreviation: S.J. or SJ), also known as the Jesuit Order or the Jesuits ( ; ), is a religious order (Catholic), religious order of clerics regular of pontifical right for men in the Catholic Church headquartered in Rom ...

in 1846, and from 1850 to 1856 and from 1862 to 1871 he was Professor of Mathematics at various Jesuit colleges. He was appointed Professor of

Canon Law Canon law (from , , a 'straight measuring rod, ruler') is a set of ordinances and regulations made by ecclesiastical jurisdiction, ecclesiastical authority (church leadership) for the government of a Christian organization or church and its membe ...

in 1873, moving to

Rome Rome (Italian language, Italian and , ) is the capital city and most populated (municipality) of Italy. It is also the administrative centre of the Lazio Regions of Italy, region and of the Metropolitan City of Rome. A special named with 2, ...

in 1880. He died in

Lyon Lyon (Franco-Provençal: ''Liyon'') is a city in France. It is located at the confluence of the rivers Rhône and Saône, to the northwest of the French Alps, southeast of Paris, north of Marseille, southwest of Geneva, Switzerland, north ...

at the age of 77. His work centred on

number theory Number theory is a branch of pure mathematics devoted primarily to the study of the integers and arithmetic functions. Number theorists study prime numbers as well as the properties of mathematical objects constructed from integers (for example ...

. In 1876 he found a new proof of

Fermat's Last Theorem In number theory, Fermat's Last Theorem (sometimes called Fermat's conjecture, especially in older texts) states that no three positive number, positive integers , , and satisfy the equation for any integer value of greater than . The cases ...

for ''n'' = 7, and in 1880 he published the first general solution to Frénicle de Bessy's problem :''x''² + ''y''² = ''z''², ''x''² = ''u''² + ''v''², ''x'' − ''y'' = ''u'' − ''v''. He also gave his name to

Pépin's test In mathematics, Pépin's test is a primality test, which can be used to determine whether a Fermat number is prime. It is a variant of Proth's test. The test is named after a French mathematician, Théophile Pépin. Description of the test Let ...

, a test of primality for

Fermat number In mathematics, a Fermat number, named after Pierre de Fermat (1601–1665), the first known to have studied them, is a natural number, positive integer of the form:F_ = 2^ + 1, where ''n'' is a non-negative integer. The first few Fermat numbers ...

References

Bibliography

* Franz Lemmermeyer. "A Note on Pépin's counter examples to the Hasse principle for curves of genus 1." ''Abh. Math. Sem. Hamburg'' 69 (1999), 335–345. 1826 births 1904 deaths French mathematicians French number theorists 19th-century French Jesuits {{France-mathematician-stub