# Hans Riesel

Hans Riesel ( born 1929 in Stockholm) is a Swedish mathematician who deals with numerical mathematics and algorithmic number theory.

## Life

Hans Riesel studied mathematics and numerical analysis at the University of Stockholm. In the 1950s he was involved in the programming of the first Swedish electronic computer BESK (Binary electronic sequence calculator ), which until 1966 was of 1953 in operation and which was founded after the war, the Swedish Computer Society ( sbek, Swedish Board of Computing Machinery ) carried been. 1960 to 1963 he headed the mathematics department of the sbek and was then in its successor organization Safad until 1969. Afterwards, he was Professor of Numerical Analysis at the Technical University in Stockholm.

In 1957, he was the 18th Mersenne prime.

According to him, the trickle figures are named, of which he discovered in 1956 with 509 203 Probably the smallest Riesel number.

## Publications

- Prime Numbers and Computer Methods for Factorization. Birkhäuser, Stuttgart 1985, ISBN 3-7643-3291-3. (2nd edition 1994, ISBN 3-7643-3743-5 ).