Ulam spiral generator (see http://en.wikipedia.org/wiki/Ulam_spiral) made with python, using PIL.
Ulam spiral is a representation of prime numbers in a spiral shape. This brings diagonals shapes out from a sequence which seems to be random.
TODO:
- See code comments
- Test an odd-black spiral, removing 5 and 3 multiples, and randomize apparition for remaining numbers. Just to test something about comments on this video : http://www.youtube.com/watch?v=iFuR97YcSLM