a version of the famous $n!+1=m^2$ problem

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It is still unknown if $n!+1=m^2$ has only 3 solutions, i.e. for $n=4,5,7$.

$n!+1$ being a perfect square

https://en.wikipedia.org/wiki/Brocard%27s_problem


What about my problem:

Are there finitely or infinitely many numbers $n$ such that $n!+1$ is divisible by a perfect square greater than 1?

It is also interesting if $n!+1$ is squarefree for infinitely many $n$.


For $n\le 100$, number $n!+1$ is:

  • prime for $n=1,2,3,11,27,37,41,73,77$

  • perfect square for $n=4,5,7$

  • divisible by a square (while not being a perfect square) for $n=12,23$

  • composite squarefree for other $n$'s