SageMath
Free, open-source math software supporting research and teaching in algebra, geometry, number theory, cryptography and numerical computation.
Sage is free, open-source math software that supports research and teaching in algebra, geometry, number theory, cryptography, numerical computation, and related areas.. The overall goal of Sage is to create a viable, free, open-source alternative to Maple, Mathematica, Magma, and MATLAB.
For help, start with the SageMath tutorial.
SageMath
Download for Windows, Mac and Linux