%I #19 Aug 19 2022 20:22:01
%S 1,0,0,0,24,240,1560,8400,60984,912240,15938520,242998800,3300493944,
%T 44583979440,690641504280,12868117189200,264164524958904,
%U 5481631005177840,112822632387018840,2367468210865875600,52624238539033647864,1258531092544541563440
%N Expansion of e.g.f. exp((exp(x) - 1)^4).
%F E.g.f.: exp((exp(x) - 1)^4).
%F G.f.: Sum_{k>=0} (4*k)! * x^(4*k)/(k! * Product_{j=1..4*k} (1 - j * x)).
%F a(0) = 1; a(n) = 24 * Sum_{k=1..n} binomial(n-1,k-1) * Stirling2(k,4) * a(n-k).
%F a(n) = Sum_{k=0..floor(n/4)} (4*k)! * Stirling2(n,4*k)/k!.
%o (PARI) my(N=30, x='x+O('x^N)); Vec(serlaplace(exp((exp(x)-1)^4)))
%o (PARI) my(N=30, x='x+O('x^N)); Vec(sum(k=0, N, (4*k)!*x^(4*k)/(k!*prod(j=1, 4*k, 1-j*x))))
%o (PARI) a_vector(n) = my(v=vector(n+1)); v[1]=1; for(i=1, n, v[i+1]=24*sum(j=1, i, binomial(i-1, j-1)*stirling(j, 4, 2)*v[i-j+1])); v;
%o (PARI) a(n) = sum(k=0, n\4, (4*k)!*stirling(n, 4*k, 2)/k!);
%Y Cf. A000110, A052859, A353664.
%Y Cf. A327505, A353358, A353775.
%K nonn
%O 0,5
%A _Seiichi Manyama_, May 07 2022