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"How many ways can a math professor incorrectly address Christmas cards so that no card gets to the originally intended recipient"

I found a recurrence formula but don`t know how to implement it in Mathematica, this is the formula:

N(n)=(n-1)[N(n-2)+(n-2)[N(n-3)+(n-3)[N(n-4)+(n-4)[...]]]]

thank you