Actually 2**N is the number of subsets of a set of cardinality N, while the number of permutations of a set of N distinct elements is N! (facultyfactorial).

ivancho used the subset theme quite succesfully in this node above.

In a way you are correct, except that it's "factorial" not "faculty" - I used the word permutations a bit too loosely.

However, the module Math::Combinatorics can still be used to iterate through the 2**N subsets as well as the nCr combinations and the N! permutations.

Thank you, for pointing me to the "factorial"
Note to self: Don't transfer mathematical/technical terms from German to English without consulting a dictionary first.

Also, would you be able to give example code for the subset iteration with Math::Combinatorics?

If there is an easy way to do so, it has escaped me.

The closest I saw in the docs was that example to generate:
"Morse signals: diferent signals of 3 positions using the two symbols - and .".

Now Morse signals of length 3 are surely one-to-one and onto the subsets of a 3 element set (set elements = pos in signal; element not/contained = dot/dash)

The given iteration using next_multiset and next_string is like computing 2**n as sum_k=0..n nCk

At least this is not trivial application of the modules methods.