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 A366594 #11 Oct 14 2023 13:19:55
%S A366594 1,0,0,1,3,3,5,24,60,102,258,816,1992,4452,12012,33617,84627,212823,
%T A366594 577361,1561077,4063059,10715009,29052015,78235107,208358693,
%U A366594 560561391,1522609569,4120277283,11129752269,30240233739,82441619605,224488878600,611770878012
%N A366594 G.f. A(x) satisfies A(x) = 1 + x^3*(1+x)^3*A(x)^4.
%F A366594 a(n) = Sum_{k=0..floor(n/3)} binomial(3*k,n-3*k) * binomial(4*k,k)/(3*k+1).
%o A366594 (PARI) a(n) = sum(k=0, n\3, binomial(3*k, n-3*k)*binomial(4*k, k)/(3*k+1));
%Y A366594 Cf. A366272, A366593, A366595.
%Y A366594 Cf. A366588, A366591.
%Y A366594 Cf. A366557.
%K A366594 nonn
%O A366594 0,5
%A A366594 _Seiichi Manyama_, Oct 14 2023