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 A357594 #14 Oct 05 2022 10:09:12
%S A357594 0,0,1,3,12,60,362,2562,20820,191088,1955020,22061380,272197160,
%T A357594 3645227040,52656804440,816114251400,13508168448400,237805776169600,
%U A357594 4436759277524400,87445191383773200,1815460566861236000,39600109151685600000,905416958295793788000
%N A357594 Expansion of e.g.f. log(1-x) * tan(log(1-x)/2).
%F A357594 a(n) = 2 * Sum_{k=0..floor(n/2)} (-1)^k * (1-4^k) * |Stirling1(n,2*k)| * Bernoulli(2*k).
%F A357594 a(n) ~ n! * 2*Pi / (exp(Pi) * (1 - exp(-Pi))^(n+1)). - _Vaclav Kotesovec_, Oct 05 2022
%o A357594 (PARI) my(N=30, x='x+O('x^N)); concat([0, 0], Vec(serlaplace(log(1-x)*tan(log(1-x)/2))))
%o A357594 (PARI) a(n) = 2*sum(k=0, n\2, (-1)^k*(1-4^k)*abs(stirling(n, 2*k, 1))*bernfrac(2*k));
%Y A357594 Cf. A136128, A357591.
%K A357594 nonn
%O A357594 0,4
%A A357594 _Seiichi Manyama_, Oct 05 2022