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%I #9 Jul 17 2020 22:31:00
%S 1,1,17,1459,395793,262131251,359993423843,915919888063853,
%T 3975467425523532305,27639424688447366285203,
%U 292886774320942590679779267,4544030770812055230064359134573,99847457331663057820508375752459491,3021907600842518917755426740899056448141
%N a(0) = 1; a(n) = Sum_{k=0..n-1} binomial(n,k)^4 * a(k).
%H Seiichi Manyama, <a href="/A336196/b336196.txt">Table of n, a(n) for n = 0..143</a>
%F a(n) = (n!)^4 * [x^n] 1 / (1 - Sum_{k>=1} x^k / (k!)^4).
%t a[0] = 1; a[n_] := a[n] = Sum[Binomial[n, k]^4 a[k], {k, 0, n - 1}]; Table[a[n], {n, 0, 13}]
%t nmax = 13; CoefficientList[Series[1/(1 - Sum[x^k/(k!)^4, {k, 1, nmax}]), {x, 0, nmax}], x] Range[0, nmax]!^4
%Y Column k=4 of A326322.
%Y Cf. A000670, A102221, A336195, A336197.
%K nonn
%O 0,3
%A _Ilya Gutkovskiy_, Jul 11 2020
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