(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

5.10. Definition.Apermutationof a finite set S is a bijection from S to itself. Theword formof a permutation of [n] is the list obtained by writing the image of i in position i. We write n!, read as "nfactorial", to mean n*(n-1)*(n-2)* ... *2*1.

2. Relevant equations

None

3. The attempt at a solution

Please explain the mumbo jumbo before the last sentence.

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# Homework Help: Explain this to me as if I were 5 years old

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