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 A366241 #10 Oct 05 2023 08:35:13
%S A366241 1,2,10,72,552,4593,40185,364413,3395217,32305005,312589540,
%T A366241 3066565720,30430287693,304907935707,3080617021926,31349533179726,
%U A366241 321038696185371,3305935381202847,34211612434972446,355605873560512974,3710978684625678870
%N A366241 G.f. A(x) satisfies A(x) = 1 + x + x*(1 + x)^4*A(x)^3.
%F A366241 a(n) = Sum_{k=0..n} binomial(6*k+1,n-k) * binomial(3*k,k)/(2*k+1).
%o A366241 (PARI) a(n) = sum(k=0, n, binomial(6*k+1, n-k)*binomial(3*k, k)/(2*k+1));
%Y A366241 Cf. A364336, A366239, A366240.
%Y A366241 Cf. A366222.
%K A366241 nonn
%O A366241 0,2
%A A366241 _Seiichi Manyama_, Oct 05 2023