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 A379285 #12 Dec 20 2024 02:45:48
%S A379285 1,2,13,115,1175,13052,153115,1866599,23414063,300238945,3917984904,
%T A379285 51862207151,694670871393,9398137507922,128235826442635,
%U A379285 1762706644013297,24386388751113511,339295523459625535,4744546261930628062,66644485202547680010,939916204595095866644
%N A379285 G.f. A(x) satisfies A(x) = 1/((1 - x*A(x)^2) * (1 - x*A(x)^3)).
%F A379285 a(n) = Sum_{k=0..n} binomial(2*n+2*k+1,k) * binomial(3*n,n-k)/(2*n+2*k+1).
%o A379285 (PARI) a(n) = sum(k=0, n, binomial(2*n+2*k+1, k)*binomial(3*n, n-k)/(2*n+2*k+1));
%Y A379285 Cf. A118969, A199475, A379209, A379284, A379286, A379287.
%K A379285 nonn
%O A379285 0,2
%A A379285 _Seiichi Manyama_, Dec 19 2024