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 A385649 #10 Jul 06 2025 10:39:35
%S A385649 1,8,352,29696,4263424,1049470976,462206058496,380751228633088,
%T A385649 605491779706159104,1892234112450731442176,11725274627114715154743296,
%U A385649 144692808471111027067403108352,3563512028948515548768609167736832,175339259291213196115801459160952864768
%N A385649 G.f. A(x) satisfies A(x) = 1/( 1 - x*(A(x) + A(2*x))^3 ).
%F A385649 a(0) = 1; a(n) = Sum_{i, j, k, l>=0 and i+j+k+l=n-1} (2^j+1) * (2^k+1) * (2^l+1) * a(i) * a(j) * a(k) * a(l).
%Y A385649 Cf. A385617, A385648.
%Y A385649 Cf. A171193, A385651.
%K A385649 nonn
%O A385649 0,2
%A A385649 _Seiichi Manyama_, Jul 06 2025