Could you please clarify rule #3?

More specifically: What are the boundaries of mathematics? Do you include statistics? Stochastic signals? Signal processing algorithms? Signal processing?

Programming algorithms and their complexities (such as algorithm for shortest path)? Data structures and sorting/search?

Numerical math? Approximations? Algorithms for solving large systems (linear/nonlinear/whatever) (presumably implemented in a computer)?

Probability theory? Modelling reality, or only purely theoretical?

Cryptographic algorithms are nearly entirely mathematical, so maybe they are welcome?

My forum sucks :(, I'll be editing the rules in a bit to fix that.