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 A365972 #9 Sep 24 2023 09:16:05
%S A365972 1,0,1,0,3,0,15,720,105,25920,945,712800,39927195,18532800,4522138335,
%T A365972 486486000,324696683025,20936022307200,19281559579425,
%U A365972 5026330152043200,1045172736969075,704618287875216000,51145202778981886575,76432873129004106000
%N A365972 Expansion of e.g.f. exp( Sum_{k>=0} x^(5*k+2) / (5*k+2) ).
%F A365972 a(0) = 1; a(n) = (n-1)! * Sum_{k=0..floor((n-2)/5)} a(n-5*k-2)/(n-5*k-2)!.
%o A365972 (PARI) my(N=30, x='x+O('x^N)); Vec(serlaplace(exp(sum(k=0, N\5, x^(5*k+2)/(5*k+2)))))
%Y A365972 Cf. A000166, A365971.
%Y A365972 Cf. A365979.
%K A365972 nonn
%O A365972 0,5
%A A365972 _Seiichi Manyama_, Sep 23 2023