I've heard of Mathematica and Mathlab. Also I haven't seen any post dedicating for helping find a software so... I'm looking for a function that allows me to do math, including writing my own functions and algorithms. This may or not be a software dedicated to math but it'd really help if it is free. An example of the possibly messiest things I may want to do is a lot of recursion, example: For function A find function B: Algorithm to find B: -Compute A(1). -Define a function C based on A(1). -Compute C(A(1)) -Define a function D based on C(A(1)) Keep doing this 5 times and the last function is B.