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 A354276 #6 May 23 2022 09:12:25
%S A354276 1,0,2,-8,64,-304,3968,-43392,378880,-4002816,68247552,-995736576,
%T A354276 15949529088,-238273241088,4760383438848,-113132156780544,
%U A354276 2119956936523776,-42743492966350848,1123874181449515008,-28901050300546154496,722523072906903158784,-19401957422023594475520,589068777481530305937408
%N A354276 Product_{n>=1} (1 + x^n)^(a(n)/n!) = 1 + arctanh(x).
%F A354276 E.g.f.: Sum_{k>=1} A067856(k) * log(1 + arctanh(x^k)) / k.
%t A354276 b[n_, i_] := b[n, i] = If[n == 0, 1, If[i < 1, 0, Sum[Binomial[c[i], j] b[n - i j, i - 1], {j, 0, n/i}]]]; c[n_] := c[n] = Mod[n, 2]/n - b[n, n - 1]; a[n_] := n! c[n]; Table[a[n], {n, 1, 23}]
%Y A354276 Cf. A010050, A067856, A353821, A353928, A353972, A354118, A354176, A354274, A354275.
%K A354276 sign
%O A354276 1,3
%A A354276 _Ilya Gutkovskiy_, May 22 2022