FUNCTION: Desc2ListPerm - generate all permutations with a given descent set

CALLING SEQUENCE:

Desc2ListPerm(desc, n)

SG[Desc2ListPerm](desc, n)

PARAMETERS:

desc = any list of positive integer

n = any positive integer denoting the degree of a symmetric group

SYNOPSIS:

• The Desc2ListPerm function generates all permutations having a given descent set desc.

• The result is a list of permutations in lexicographic order.

• Whenever there is a conflict between the function name Desc2ListPerm and another name used in the same session, use the long form SG['Desc2ListPerm'].

EXAMPLES:

> with(SG):
> Desc2ListPerm([1,2,4], 5);
 
  [[3, 2, 1, 5, 4], [4, 2, 1, 5, 3], [4, 3, 1, 5, 2], [4, 3, 2, 5, 1],
 
   [5, 2, 1, 4, 3], [5, 3, 1, 4, 2], [5, 3, 2, 4, 1], [5, 4, 1, 3, 2],
 
   [5, 4, 2, 3, 1]]