# Permutation

In combinatorics, a permutation is a rearrangement of the elements in an ordered list *S* into a one-to-one correspondence with *S* itself. Combinatorics studies the number of possible ways of doing this under various conditions.

Permutation is a college-level concept that would be first encountered in a discrete mathematics course covering combinatorics. It is listed in the California State Standards for Algebra II.

### Prerequisites

Factorial: | The factorial of a positive integer n, denoted n!, is the product of the first n positive integers. |