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 A366215 #8 Oct 04 2023 12:51:07
%S A366215 1,5,26,200,1995,22522,272152,3437280,44806905,598204475,8137535934,
%T A366215 112382617018,1571496538035,22205618546014,316570999534832,
%U A366215 4547819503936622,65770112191659609,956743348385310031,13989838139093922658,205511713513718581234
%N A366215 G.f. A(x) satisfies A(x) = 1/(1 - x)^4 + x*(1 - x)^4*A(x)^4.
%F A366215 a(n) = Sum_{k=0..n} binomial(n+7*k+3,n-k) * binomial(4*k,k)/(3*k+1).
%o A366215 (PARI) a(n) = sum(k=0, n, binomial(n+7*k+3, n-k)*binomial(4*k, k)/(3*k+1));
%Y A366215 Cf. A014140, A164965, A366034.
%K A366215 nonn
%O A366215 0,2
%A A366215 _Seiichi Manyama_, Oct 04 2023