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 A364589 #10 Jul 29 2023 10:38:39
%S A364589 1,1,1,2,4,7,14,31,67,146,331,760,1749,4072,9583,22673,53929,129055,
%T A364589 310328,749152,1815481,4415313,10771564,26352955,64644926,158963191,
%U A364589 391767016,967523138,2394060433,5934576763,14735792889,36647185192,91274339014,227645446307
%N A364589 G.f. satisfies A(x) = 1/(1-x) + x^3*A(x)^3.
%F A364589 a(n) = Sum_{k=0..floor(n/3)} binomial(n-k,2*k) * binomial(3*k,k) / (2*k+1).
%o A364589 (PARI) a(n) = sum(k=0, n\3, binomial(n-k, 2*k)*binomial(3*k,k)/(2*k+1));
%Y A364589 Cf. A216604, A226974.
%Y A364589 Cf. A049130, A199475, A364590.
%K A364589 nonn,easy
%O A364589 0,4
%A A364589 _Seiichi Manyama_, Jul 29 2023