permutation (ˌpɜːmjʊˈteɪʃən) | |
—n | |
1. | maths |
a. an ordered arrangement of the numbers, terms, etc, of a set into specified groups: the permutations of a, b, and c, taken two at a time, are ab, ba, ac, ca, bc, cb | |
b. Compare combination _{n}P_{r} a group formed in this way. The number of permutations of n objects taken r at a time is n!/(n--r)! | |
2. | a combination of items made by reordering |
3. | an alteration; transformation |
4. | Usually shortened to: perm a fixed combination for selections of results on football pools |
[C14: from Latin permūtātiō, from permūtāre to change thoroughly; see | |
permu'tational | |
—adj |