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.
%I A356393 #13 Aug 16 2022 10:16:38
%S A356393 1,1,4,27,188,1730,18234,220206,2958416,44470296,729675720,
%T A356393 13002636240,249986061192,5154030469848,113360272804128,
%U A356393 2648908519611480,65477559553098240,1707034986277780800,46798324479957887424,1345365460101611611584
%N A356393 Expansion of e.g.f. ( Product_{k>0} (1+x^k) )^(1/(1-x)).
%H A356393 Seiichi Manyama, <a href="/A356393/b356393.txt">Table of n, a(n) for n = 0..434</a>
%F A356393 a(0) = 1; a(n) = Sum_{k=1..n} A356390(k) * binomial(n-1,k-1) * a(n-k).
%o A356393 (PARI) my(N=20, x='x+O('x^N)); Vec(serlaplace(prod(k=1, N, 1+x^k)^(1/(1-x))))
%o A356393 (PARI) a356390(n) = n!*sum(k=1, n, sumdiv(k, d, (-1)^(k/d+1)*d)/k);
%o A356393 a_vector(n) = my(v=vector(n+1)); v[1]=1; for(i=1, n, v[i+1]=sum(j=1, i, a356390(j)*binomial(i-1, j-1)*v[i-j+1])); v;
%Y A356393 Cf. A356392, A356394.
%Y A356393 Cf. A000009, A356335, A356390.
%K A356393 nonn
%O A356393 0,3
%A A356393 _Seiichi Manyama_, Aug 05 2022