Modules
Some useful math functions. These are generally used internally by the library.
The lazy sequence of results returned by SComb.permutations/1,
SComb.combinations/2, SComb.subsets/1, SComb.selections/2,
SComb.partitions/1, SComb.combinations_with_replacement/2,
SComb.permuted_combinations/2 and SComb.cartesian_product/1.