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 A361558 #9 Mar 15 2023 12:40:26
%S A361558 1,1,4,20,127,976,8776,90084,1037555,13233077,184956386,2809098986,
%T A361558 46038214729,809411443790,15189361799522,302932433571356,
%U A361558 6396529241755881,142523960797017589,3341115707515530400,82187749261419720712,2116421112495023612311
%N A361558 Expansion of e.g.f. exp((x + x^2/2 + x^3/6 + x^4/24)/(1-x)).
%F A361558 a(n) = (2*n-1) * a(n-1) - (n-1)*(n-3) * a(n-2) - binomial(n-1,3) * a(n-4) - 3*binomial(n-1,4) * a(n-5) for n > 4.
%o A361558 (PARI) my(N=30, x='x+O('x^N)); Vec(serlaplace(exp((x+x^2/2+x^3/6+x^4/24)/(1-x))))
%Y A361558 Cf. A361532, A361548, A361557.
%K A361558 nonn
%O A361558 0,3
%A A361558 _Seiichi Manyama_, Mar 15 2023