URL: http://www.bway.net/~lewis
Contact: rlewis at fordham dot edu

Fermat is a computer algebra system for Macintosh, Linux, Unix, and Windows by Robert H. Lewis of Fordham University, that does arithmetic of arbitrarily long integers and fractions, symbolic calculations, matrices over polynomial rings, graphics, and other numerical calculations. The main version is oriented toward polynomial and matrix algebra over the rationals and finite fields.