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 A355411 #11 Jul 01 2022 12:11:08
%S A355411 1,5,63,1175,29211,907775,33852603,1472830175,73232729451,
%T A355411 4096474833695,254608472798043,17407167078420575,1298290575826434891,
%U A355411 104900562662494154015,9127848307446874753083,850985644429074730049375,84626187772620135685119531
%N A355411 Expansion of e.g.f. 1/(3 - exp(2*x) - exp(3*x)).
%F A355411 a(0) = 1; a(n) = Sum_{k=1..n} (3^k + 2^k) * binomial(n,k) * a(n-k).
%F A355411 a(n) ~ n! / ((9 - r^2) * log(r)^(n+1)), where r = (-1 + 2*cosh(log((79 + 9*sqrt(77))/2)/3))/3. - _Vaclav Kotesovec_, Jul 01 2022
%o A355411 (PARI) my(N=20, x='x+O('x^N)); Vec(serlaplace(1/(3-exp(2*x)-exp(3*x))))
%o A355411 (PARI) a_vector(n) = my(v=vector(n+1)); v[1]=1; for(i=1, n, v[i+1]=sum(j=1, i, (3^j+2^j)*binomial(i, j)*v[i-j+1])); v;
%Y A355411 Cf. A355380, A355409.
%K A355411 nonn
%O A355411 0,2
%A A355411 _Seiichi Manyama_, Jul 01 2022