Sage Math - Sage is a free open-source mathematics software system licensed under the GPL.

PARI/GP - PARI/GP is a widely used computer algebra system designed for fast computations in number theory - factorizations, algebraic number theory, elliptic curves, modular forms, L functions..

Cadabra - Cadabra is the name of a universal computer algebra system designed for those users looking for the solution to problems encountered in the filed theory.

GNU Octave - GNU Octave is a programming language for scientific computing.

Maxima - Maxima is a fairly complete computer algebra system written in Lisp with an emphasis on symbolic computation.

Wolfram Mathematica - Mathematica has characterized the cutting edge in specialized processing—and gave the chief calculation environment to a large number of pioneers, instructors, understudies, and others around the globe.