I was given this problem:
Given a set of $n$ elements, how many possible involutions can we form?
I have managed to device this recurrence relation: $$t_n=t_{n-1}+(n-1)t_{n-2}$$ How can I form a closed form equation for this?
2026-04-08 04:10:41.1775621441
Closed form of a recurrence relation
55 Views Asked by Bumbble Comm https://math.techqa.club/user/bumbble-comm/detail AtRelated Questions in COMBINATORICS
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