What is an odd permutation?

A permutation that can be written as a product of an odd number of transpositions (swaps). Sign = -1.

How many odd permutations are there?

For n ≥ 2, exactly half of n! permutations are odd: n!/2. For n = 1, there are 0.

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Count how many permutations of n objects are odd (expressible as an odd number of swaps). For n ≥ 2, equals n!/2.

n (number of objects)

What is an odd permutation?: A permutation that can be written as a product of an odd number of transpositions (swaps). Sign = -1.
How many odd permutations are there?: For n ≥ 2, exactly half of n! permutations are odd: n!/2. For n = 1, there are 0.
Is this tool free?: Yes. All tools on QuickFreeTools are free with no signup.

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