Herbert John Ryser

Herbert John Ryser (1923 to 1985) was a mathematics professor widely regarded as one of the major figures in twentieth century combinatorics. His name is attached to the Bruck-Ryser-Chowla theorem on finite projective planes, to Ryser's formula for computing the permanent of a matrix, and to Ryser's conjecture. He took his bachelor, master and doctoral degrees at the University of Wisconsin, finishing in 1948 with a thesis on rational vector spaces, and after a year at the Institute for Advanced Study he taught at Ohio State University, Syracuse University and from 1967 at Caltech. He contributed to the theory of combinatorial designs, finite set systems and the permanent, wrote the Carus monograph Combinatorial Mathematics, and edited several journals including the Journal of Combinatorial Theory.