--  PERMUT returns the number of permutations for a given
--  number of items selected from a number of objects.
--  A permutation is any set or subset of objects where the
--  internal order is relevant.
--
--  Use COMBIN for the number of combinations, 
--  where the internal order is not relevant.
--
--  PERMUT implements this calculation:
--  P(n,k) = n! / (n-k)!
--
--  For example, consider 3 elements ( A, B, C )
--  PERMUT ( 3, 2 ) returns 6 counting:
--       ( A, B )
--       ( B, A )
--       ( B, C )
--       ( C, B )
--       ( A, C )
--       ( C, A )
EVALUATE 
{
    ( "PERMUT ( 2, 1 )", PERMUT ( 2, 1 ) ),
    ( "PERMUT ( 2, 2 )", PERMUT ( 2, 2 ) ),
    ( "PERMUT ( 3, 1 )", PERMUT ( 3, 1 ) ),
    ( "PERMUT ( 3, 2 )", PERMUT ( 3, 2 ) ),
    ( "PERMUT ( 3, 3 )", PERMUT ( 3, 3 ) ),
    ( "PERMUT ( 4, 1 )", PERMUT ( 4, 1 ) ),
    ( "PERMUT ( 4, 2 )", PERMUT ( 4, 2 ) ),
    ( "PERMUT ( 4, 3 )", PERMUT ( 4, 3 ) ),
    ( "PERMUT ( 4, 4 )", PERMUT ( 4, 4 ) )
}