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 A385468 #13 Jun 30 2025 04:13:17
%S A385468 1,1,3,17,129,1269,15147,213765,3475329,64020585,1317472563,
%T A385468 29960707545,746086414785,20192521440285,590166330458715,
%U A385468 18525204423695565,621571306435103745,22199954036873457105,840913892465144800995,33672216851574639900705
%N A385468 Expansion of e.g.f. 1/(1 - 2 * arctanh(x))^(1/2).
%F A385468 E.g.f.: 1/(1 - log((1+x)/(1-x)))^(1/2).
%F A385468 a(n) = Sum_{k=0..n} A001147(k) * A111594(n,k).
%F A385468 a(n) ~ 2 * (exp(1) + 1)^(n - 1/2) * n^n / (exp(n - 1/2) * (exp(1) - 1)^(n + 1/2)). - _Vaclav Kotesovec_, Jun 30 2025
%o A385468 (PARI) my(N=20, x='x+O('x^N)); Vec(serlaplace(1/(1-2*atanh(x))^(1/2)))
%Y A385468 Cf. A296676, A385469.
%Y A385468 Cf. A001147, A111594, A385376.
%K A385468 nonn,easy
%O A385468 0,3
%A A385468 _Seiichi Manyama_, Jun 30 2025