http://www.sagemath.org/ should be visited by anyone interested in helping promote (including R) open source software that is numerical in nature. I agree that programming is important if you need answers to tough (realistic) math questions, and SageMath will allow you to explore a number of open-source packages ( NumPy, SciPy, matplotlib, Sympy, Maxima, GAP, FLINT, R, etc.). Really, SageMath needs more users . . . please help!