Recursive Swapping

I'm writing a recursive program that accepts an input and prints out all n! permutations of the n letters starting at "a". A permutation of n elements is one of the n! possible orderings of the elements.

meaning i need to have a sample output like ....

bca cba cab acb bac abc

if i enter n=3....

could anyone help me out on what keywords i should u use ?
I'm thiniking of doin it wit a resursive program and array swapping ....

Thanks .... :P

a + all permutations of "bc"
b + all permutations of "ac"
c + all permutations of "ab"

The first one them becomes
b + all permutations of "c"
c + all permutations of "b"

All permutations of a single letter are the trivial answer which stops the recursion.