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 A379187 #7 Dec 18 2024 09:27:58
%S A379187 1,4,30,286,3091,36063,442898,5642628,73893561,988585443,13453580815,
%T A379187 185661101085,2592069904059,36545520229810,519601325300487,
%U A379187 7441580996167052,107255985242888943,1554576968046707916,22644622298400113411,331322620547205661043
%N A379187 G.f. A(x) satisfies A(x) = 1/((1 - x*A(x)^2) * (1 - x*A(x))^3).
%F A379187 a(n) = Sum_{k=0..n} binomial(n+2*k+1,k) * binomial(4*n+2*k+2,n-k)/(n+2*k+1).
%o A379187 (PARI) a(n) = sum(k=0, n, binomial(n+2*k+1, k)*binomial(4*n+2*k+2, n-k)/(n+2*k+1));
%Y A379187 Cf. A118971, A369617, A379188.
%Y A379187 Cf. A369215.
%K A379187 nonn
%O A379187 0,2
%A A379187 _Seiichi Manyama_, Dec 17 2024