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 A366179 #9 Oct 03 2023 08:59:57
%S A366179 1,3,13,80,582,4627,38906,340138,3060404,28151835,263546436,
%T A366179 2502686416,24048985907,233410500126,2284790496700,22530585455108,
%U A366179 223610524426654,2231886642819974,22389017726854323,225604735477075272,2282518274913713101
%N A366179 G.f. A(x) satisfies A(x) = 1/(1 - x)^2 + x*A(x)^3/(1 - x).
%F A366179 a(n) = Sum_{k=0..n} binomial(n+4*k+1,n-k) * binomial(3*k,k)/(2*k+1).
%o A366179 (PARI) a(n) = sum(k=0, n, binomial(n+4*k+1, n-k)*binomial(3*k, k)/(2*k+1));
%Y A366179 Partial sums of A366178.
%Y A366179 Cf. A364620, A364629, A366180.
%K A366179 nonn
%O A366179 0,2
%A A366179 _Seiichi Manyama_, Oct 03 2023