Hugo van der Sanden
I am a professional programmer, and a recreational mathematician with particular interest in Number Theory.
13 What's the simplest rational not expressible as a sum of a given number of unit fractions? sep 14 '10
9 A balls-and-colours problem oct 13 '10
5 Are there primes p, q such that p^4+1 = 2q^2 ? may 14 '10
2 How to characterize a Self-avoiding path. oct 10 '10
1 other examples of composition of functions jun 9 '10