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 A371615 #10 Mar 30 2024 02:36:10
%S A371615 1,2,5,34,222,1622,12559,100904,835322,7070574,60922335,532566850,
%T A371615 4711614912,42106192680,379544358032,3446755447528,31504896429042,
%U A371615 289619348156494,2675953520657839,24836797229730316,231461661673958896,2165002179076830442
%N A371615 G.f. satisfies A(x) = ( 1 + x / (1 - x*A(x)^3)^2 )^2.
%F A371615 a(n) = Sum_{k=0..n} binomial(6*(n-k)+2,k) * binomial(n+k-1,n-k)/(3*(n-k)+1).
%o A371615 (PARI) a(n, r=2, s=2, t=0, u=6) = r*sum(k=0, n, binomial(t*k+u*(n-k)+r, k)*binomial(n+(s-1)*k-1, n-k)/(t*k+u*(n-k)+r));
%Y A371615 Cf. A371613, A371617.
%K A371615 nonn
%O A371615 0,2
%A A371615 _Seiichi Manyama_, Mar 29 2024