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 A375808 #12 Sep 01 2024 10:14:05
%S A375808 1,2,6,24,144,1080,9360,94080,1078560,13789440,194745600,3013718400,
%T A375808 50654419200,918900702720,17896250211840,372338481715200,
%U A375808 8241399758592000,193366506222489600,4793430516921446400,125181207625240166400,3435031723216084992000
%N A375808 Expansion of e.g.f. 1/(1 + (log(1 - x^3))/x^2)^2.
%F A375808 E.g.f.: B(x)^2, where B(x) is the e.g.f. of A375799.
%F A375808 a(n) = n! * Sum_{k=0..floor(n/3)} (n-3*k+1)! * |Stirling1(n-2*k,n-3*k)|/(n-2*k)!.
%o A375808 (PARI) my(N=30, x='x+O('x^N)); Vec(serlaplace(1/(1+log(1-x^3)/x^2)^2))
%o A375808 (PARI) a(n) = n!*sum(k=0, n\3, (n-3*k+1)!*abs(stirling(n-2*k, n-3*k, 1))/(n-2*k)!);
%Y A375808 Cf. A375799, A375809.
%K A375808 nonn
%O A375808 0,2
%A A375808 _Seiichi Manyama_, Aug 29 2024