The Scientist and Engineer's Guide to Digital Signal Processing - good resource
math electronics book reference
Discussion of the Deolalikar N!=NP paper
math
HP researcher Vinay Deolalikar claims to have proven that the complexity class P is not equal to the class NP. It's like the most important t unanswered question in math.
math
It has now been proved that every rubiks cube can be solved in 20 moves
math games