(October 2007) http://users.softlab.ntua.gr/~ttsiod/yield.html
Computing permutations
What is a permutation? Reading from my local copy of Wikipedia:
Permutation is the rearrangement of objects or symbols into distinguishable sequences. Each unique ordering is called a permutation. For example, with the numerals one to six, each possible ordering consists of a complete list of the numerals, without repetitions. There are 720 total permutations of these numerals, one of which is: "4, 5, 6, 1, 2, 3".