Combinat package
The functions of the combinat package are used for simple combinatorical 
calculations.  The functions available can be listed with info(combinat). 
These are

permute - permutations of a list
permute(n)
Parameters: 
   n - list or non-negative integer

powerset - power set of a set
powerset(n)
Parameters: 
   n - set or non-negative integer

stirling1 - Stirling numbers of the first kind
stirling1(n,m)
Parameters:
   non-negative integers

stirling2 - Stirling numbers of the second kind
stirling2(n,m)
Parameters:
   non-negative integers

