Christian Kramp

French mathematician- Christian Kramp (8 July 1760 â€“ 13 May 1826) was a French mathematician, who worked primarily with factorials. Christian Kramp's father was his teacher at grammar school in Strasbourg.
- Kramp studied medicine and graduated; however, his interests certainly ranged outside medicine, for in addition to a number of medical publications he published a work on crystallography in 1793.
- In 1795, France annexed the Rhineland area in which Kramp was carrying out his work and after this he became a teacher at Cologne (this city was French from 1794 to 1815), teaching mathematics, chemistry, and physics.
- Kramp could read and write in German and French.Kramp was appointed professor of mathematics at Strasbourg, the town of his birth, in 1809.
- He was elected to the geometry section of the French Academy of Sciences in 1817.
- As Bessel, Legendre and Gauss did, Kramp worked on the generalised factorial function which applied to non-integers.
- His work on factorials is independent of that of James Stirling and Vandermonde.
- He was the first to use the notation n! (Elements d'arithmÃ©tique universelle, 1808).
- In fact, the more general concept of factorial was found at the same time by Arbogast. I have given it the name 'faculty'.
- Arbogast has substituted the name 'factorial' which is clearer and more French.
- In adopting his idea I congratulate myself on paying homage to the memory of my friend.
- ...
- I use the very simple notation n! to designate the product of numbers decreasing from n to unity, i.e.
- n(n - 1)(n - 2) ...
- 3 .
- 2 .
- 1.
- The constant use in combinatorial analysis, in most of my proofs, that I make of this idea, has made this notation necessary. Kramp's function, a scaled complex error function, is today better known as the Faddeeva function.

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