$$$a_1 = 1$$$
$$$a_2 = 5$$$
$$$a_n = a_{n-1} + n^2(a_{n-2}+1)$$$
Prove $$$a_n=(n+1)!-1$$$
P.S. Original problem
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[SOLVED] How to prove reduction of this induction to formula?
Revision en3, by prudent, 2019-06-16 11:32:59
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