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%I #14 Feb 04 2022 12:21:28
%S 1,1,65,19876,16895763,30685843321,102018812632786,560682901512212459,
%T 4738032814084465062121,58320000513552476843995786,
%U 1002620283226568243192938115197,23280221638971518379191182864465213,710336441472841166799952152725333251616
%N a(0) = 1, a(n) = Sum_{k=1..n} stirling2(n,k) * k^(3*k).
%H Seiichi Manyama, <a href="/A308491/b308491.txt">Table of n, a(n) for n = 0..152</a>
%F a(n) ~ n^(3*n).
%F E.g.f.: Sum_{k>=0} (k^3 * (exp(x) - 1))^k / k!. - _Seiichi Manyama_, Feb 04 2022
%t Join[{1}, Table[Sum[k^(3*k)*StirlingS2[n, k], {k, 1, n}], {n, 1, 15}]]
%o (PARI) my(N=20, x='x+O('x^N)); Vec(serlaplace(sum(k=0, N, (k^3*(exp(x)-1))^k/k!))) \\ _Seiichi Manyama_, Feb 04 2022
%Y Cf. A282190, A308490, A316748.
%K nonn
%O 0,3
%A _Vaclav Kotesovec_, May 31 2019