Further Examples: Factorial (!)

Here is a table of the first 20 factorials.

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Here is a way to invert the factorial function. In other words, InverseFactorial[n!] gives n when n is a positive integer.

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This checks the result for the first factorials.

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There is no integer k such that k! == + .

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has approximately digits yet InverseFactorial returns the correct answer quickly.

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