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 A365908 #10 Sep 23 2023 07:28:26
%S A365908 1,0,1,0,6,1,90,42,2521,2268,113742,166321,7543206,16218930,691242553,
%T A365908 2044833336,83708046246,324830941345,12951273345282,63596620804122,
%U A365908 2493395633726425,15062005915534116,584749646165678622,4247497704703187089,164155618660742879022
%N A365908 Expansion of e.g.f. 1 / ( 1 - Sum_{k>=0} x^(3*k+2) / (3*k+2)! ).
%F A365908 a(0) = 1; a(n) = Sum_{k=0..floor((n-2)/3)} binomial(n,3*k+2) * a(n-3*k-2).
%o A365908 (PARI) my(N=30, x='x+O('x^N)); Vec(serlaplace(1/(1-sum(k=0, N\3, x^(3*k+2)/(3*k+2)!))))
%Y A365908 Cf. A032032, A365909.
%Y A365908 Cf. A365338.
%K A365908 nonn,easy
%O A365908 0,5
%A A365908 _Seiichi Manyama_, Sep 22 2023