1. A method for combinatorial coding and decoding, the method comprising the steps of: receiving a value n based on a number of positions in a vector; receiving a value d based on a number of occupied positions within the vector; generating F′(n, d) based on n and d, wherein F′(n, d) is an estimate of F(n,d) such that F′(n, d)>F(n, d) and F′(n, d)>F′(n−1, d)+F′(n−1, d−1), and wherein F ( n , d ) = n ! d ! ( n - d ) ! ; and using F′(n, d) to code or decode the vector.