Department of Mathematics FAS Harvard University One Oxford Street Cambridge MA 02138 USA Tel: (617) 495-2171 Fax: (617) 495-5132
FAS Computer Services to Harvard University IT: (617) 495-7777.
Software for Algebra and Geometry Experimentation (SAGE) is a comprehensive open-source Python-based system for mathematics. It includes other software like Maxima, Pari and Gap.

Simplicity, Clarity, Generality B.W. Kernighan, R. Pike, in "The Practice of Programming".