%I #18 Sep 01 2022 09:31:30
%S 1,0,4,27,448,10625,344736,14437213,753991680,47974773393,
%T 3650824000000,326917384798301,33956137832546304,4041303651931462969,
%U 545552768347831566336,82828479894303251953125,14040577418634835164921856,2640293357854435329683551265
%N a(n) = Sum_{k=0..n} (k*n-1)^(n-k) * binomial(n,k).
%H Seiichi Manyama, <a href="/A356806/b356806.txt">Table of n, a(n) for n = 0..274</a>
%F a(n) = n! * [x^n] exp( x * (exp(n * x) - 1) ).
%F a(n) = n! * Sum_{k=0..floor(n/2)} n^(n-k) * Stirling2(n-k,k)/(n-k)!.
%F a(n) = [x^n] Sum_{k>=0} x^k / (1 - (n*k-1)*x)^(k+1).
%o (PARI) a(n) = sum(k=0, n, (k*n-1)^(n-k)*binomial(n, k));
%o (PARI) a(n) = n!*sum(k=0, n\2, n^(n-k)*stirling(n-k, k, 2)/(n-k)!);
%Y Cf. A052506, A351736, A351737.
%Y Cf. A356811, A356814, A356817.
%K nonn
%O 0,3
%A _Seiichi Manyama_, Aug 29 2022
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