Determine the minimum value of a nonnegative integer N, such that:

            (20N)!
            ------
            (N!)21

is NOT an integer.

Provide valid reasoning to support your answer.

Note: Computer program or spreadsheet assisted methodologies are welcome, but an analytical solution is preferred.

(In reply to I think this is it. by Larry)

Larry's answer makes sense, because it is the smallest prime that is greater than 20.

Posted by Steve Herman on 2023-05-17 10:28:54