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%I #20 Mar 15 2023 15:02:44
%S 1,4,36,488,8824,199456,5410208,171209664,6192052800,251937937920,
%T 11389639660032,566394573855744,30726758349800448,1805828538127687680,
%U 114293350061315678208,7750480651439579529216,560615413313367534698496,43085423893717998388740096
%N Expansion of e.g.f. 1/(1 + 4 * log(1-x)).
%F E.g.f.: 1/(1 + 4 * log(1-x)).
%F a(0) = 1; a(n) = 4 * Sum_{k=1..n} (k-1)! * binomial(n,k) * a(n-k).
%F a(n) = Sum_{k=0..n} 4^k * k! * |Stirling1(n, k)|.
%F a(n) ~ n! * exp(n/4) / (4 * (exp(1/4) - 1)^(n+1)). - _Vaclav Kotesovec_, Jun 04 2022
%o (PARI) my(N=20, x='x+O('x^N)); Vec(serlaplace(1/(1+4*log(1-x))))
%o (PARI) a_vector(n) = my(v=vector(n+1)); v[1]=1; for(i=1, n, v[i+1]=4*sum(j=1, i, (j-1)!*binomial(i, j)*v[i-j+1])); v;
%o (PARI) a(n) = sum(k=0, n, 4^k*k!*abs(stirling(n, k, 1)));
%Y Column k=4 of A320079.
%Y Cf. A094417, A354147, A354241.
%K nonn
%O 0,2
%A _Seiichi Manyama_, May 21 2022