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 A381890 #21 May 27 2025 10:10:29
%S A381890 1,1,-3,21,-225,3207,-56821,1202099,-29558466,828401462,-26068940938,
%T A381890 910286433318,-34930741605414,1461245816594058,-66187658069563710,
%U A381890 3227353484661602866,-168557942284281821933,9388117645333487820387,-555463036269652132509113
%N A381890 Expansion of Product_{k>=1} (1 + k*x)^((1/12) * (3/4)^k).
%F A381890 G.f. A(x) satisfies A(x) = (1+x)^(1/4) * A(x/(1+x))^(3/4).
%F A381890 G.f.: exp(Sum_{k>=1} (-1)^(k-1) * A050352(k) * x^k/k).
%F A381890 G.f.: 1/B(-x), where B(x) is the g.f. of A090353.
%o A381890 (PARI) my(N=20, x='x+O('x^N)); Vec(exp(sum(k=1, N, (-1)^(k-1)*sum(j=0, k, 3^(j-1)*j!*stirling(k, j, 2))*x^k/k)))
%Y A381890 Cf. A384343, A384344, A384345.
%Y A381890 Cf. A050352, A090353.
%K A381890 sign
%O A381890 0,3
%A A381890 _Seiichi Manyama_, May 26 2025