How many ways can you list numbers $1,2,3,...,n$ so that no number $i$ is in its $ith$ place on the list?

Question

How many ways can you list numbers $1,2,3,...,n$ so that no number $i$ is in its $ith$ place on the list?

For example, $1,3,2,4$ is not a valid list since $1$ is in $1st$ place.

Answer 1

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