Overview
A permutation is an operation that takes a set of elements, and reorders them. As a simple example, the following shows a permutation of the numbers from 1 to 5.
| 1 | 2 | 3 | 4 | 5 |
| 5 | 2 | 4 | 1 | 3 |
Permutations as a Group
The set of Permutations forms a group. That is, permutations can be composed. If {% p %} is a permuation and {% q %} is a permutation, the p followed by q, written as {% qp %}, is also a permuation.