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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A354317 Expansion of e.g.f. exp(-log(1 + x)^2 / 2).

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%I A354317 #16 May 24 2022 08:11:11
%S A354317 1,0,-1,3,-8,20,-34,-126,2514,-28008,285774,-2922810,30858048,
%T A354317 -339954264,3920819748,-47319853140,596005041852,-7799132781792,
%U A354317 105344546511684,-1454910026870412,20242465245436128,-276289562032117200,3490199850169557480
%N A354317 Expansion of e.g.f. exp(-log(1 + x)^2 / 2).
%F A354317 E.g.f.: 1/(1 + x)^(log(1 + x)/2).
%F A354317 a(0) = 1; a(n) = -Sum_{k=1..n} binomial(n-1,k-1) * Stirling1(k,2) * a(n-k).
%F A354317 a(n) = Sum_{k=0..floor(n/2)} (2*k)! * Stirling1(n,2*k)/((-2)^k * k!).
%o A354317 (PARI) my(N=30, x='x+O('x^N)); Vec(serlaplace(exp(-log(1+x)^2/2)))
%o A354317 (PARI) my(N=30, x='x+O('x^N)); Vec(serlaplace(1/(1+x)^(log(1+x)/2)))
%o A354317 (PARI) a_vector(n) = my(v=vector(n+1)); v[1]=1; for(i=1, n, v[i+1]=-sum(j=1, i, binomial(i-1, j-1)*stirling(j, 2, 1)*v[i-j+1])); v;
%o A354317 (PARI) a(n) = sum(k=0, n\2, (2*k)!*stirling(n, 2*k, 1)/((-2)^k*k!));
%Y A354317 Cf. A347001, A354318.
%K A354317 sign
%O A354317 0,4
%A A354317 _Seiichi Manyama_, May 24 2022