Permutation

Mathematical version of an order change

In mathematics, a permutation is a bijection of a set onto itself. It can be interpreted as a new order of the members of a sequence or linear order, or as the act or process of changing the linear order of an ordered set. An example of the first interpretation is the six permutations of the set {1, 2, 3}, which are the six 3-tuples (1, 2, 3), (1, 3, 2), (2, 1, 3), (2, 3, 1), (3, 1, 2), and (3, 2, 1).

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