John David Brillhart (November 13, 1930 – May 21, 2022) was a mathematician who worked in number theory at the University of Arizona.
[1][3] His doctoral thesis in mathematics was supervised by D. H. Lehmer, with assistance from Leonard Carlitz.
His joint work with Michael A. Morrison in 1975 describes how to implement the continued fraction factorization method originally developed by Lehmer and Ralph Ernest Powers in 1931.
[1] Brillhart was a member of the Cunningham Project, which factors Mersenne, Fermat, and related numbers.
[1] He was also a founding member and financial contributor to the Number Theory Foundation started by John L.