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 A385699 #14 Jul 07 2025 10:46:36
%S A385699 1,1,1,2,5,13,24,88,181,523,1616,4891,10540,42009,94953,294102,957259,
%T A385699 3028320,6864540,28208447,66180997,211105506,703497178,2273009790,
%U A385699 5283518340,22058432677,52795736539,171169636087,578132050147,1891182035377,4462525373212
%N A385699 G.f. A(x) satisfies A(x) = 1/( 1 - x*(A(x) + A(-x))*(A(x) + A(w*x) + A(w^2*x))/6 ), where w = exp(2*Pi*i/3).
%F A385699 a(0) = 1; a(n) = Sum_{i, j, k>=0 and i+2*j+3*k=n-1} a(i) * a(2*j) * a(3*k).
%Y A385699 Cf. A047749, A124753, A217138, A385698.
%K A385699 nonn
%O A385699 0,4
%A A385699 _Seiichi Manyama_, Jul 07 2025