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 A376547 #9 Sep 27 2024 16:33:52
%S A376547 1,0,0,1,1,0,3,6,3,12,36,36,67,220,330,493,1420,2730,4158,9933,21693,
%T A376547 36312,75684,171360,316011,617424,1374156,2723667,5256237,11303028,
%U A376547 23362779,45734304,95506488,200821140,401891490,825565455,1739179533,3549322296
%N A376547 G.f. A(x) satisfies A(x) = 1 + x^3*(1+x)*A(x)^3.
%F A376547 a(n) = Sum_{k=0..floor(n/3)} binomial(k,n-3*k) * binomial(3*k,k)/(2*k+1).
%o A376547 (PARI) a(n) = sum(k=0, n\3, binomial(k, n-3*k)*binomial(3*k, k)/(2*k+1));
%Y A376547 Cf. A017817, A366588, A376486.
%K A376547 nonn
%O A376547 0,7
%A A376547 _Seiichi Manyama_, Sep 27 2024