!! OBSOLETE !!
Its functionality is now implemented in my function PERMN, available on the File Exchange
permnsub - subset of all permutations with repetition
M = permnsub(V,N,IX) returns a subset of all permutations, with
repetition, of N elements, taken from the elements in vector V. M has
the size numel(IX)-by-N. V can be an array of numbers, cells or strings,
and M will be of the same type as V.

Use PERMN instead