A305467 a(n) = Sum_{k=0..floor(n/2)} ((n-k)!/k!)*binomial(n-k,k)*n^(n-2*k)*(-1)^k.
1, 1, 7, 150, 5857, 363045, 32817311, 4078256168, 667231014401, 139047475691385, 35961972186044999, 11303290914120251574, 4243674498966718214113, 1875719852330658989518045, 964140893268009386931042943, 570249392860305817156465883040
Offset: 0
Keywords
Links
- Seiichi Manyama, Table of n, a(n) for n = 0..232
Programs
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PARI
{a(n) = sum(k=0, n/2, ((n-k)!/k!)*binomial(n-k, k)*n^(n-2*k)*(-1)^k)}
Formula
a(n) ~ n! * n^n. - Vaclav Kotesovec, Jun 03 2018