qombinatorics - a combination and permutation calculator
qombinatorics aims to be a complete resource for combinatorics calulations.
Combinatorics, in mathematic, is the study of the many possible way to arrange a given set of objects. (http://en.wikipedia.org/wiki/Combinatorics)
Many probability calculation are possible through the knowledge of this branch of mathematics and can be easily applied to a great number of common situation, e.g. card games.