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 A367713 #8 Nov 28 2023 08:50:41
%S A367713 1,2,4,9,20,46,105,243,560,1296,2994,6928,16019,37060,85713,198282,
%T A367713 458636,1060932,2454070,5676750,13131210,30374892,70262196,162528916,
%U A367713 375957183,869654746,2011661506,4653323265,10763942479,24898869052,57595401116,133228161565
%N A367713 G.f. A(x) satisfies A(x) = 1 / ((1 - x) * (1 - x * (1 + x) * A(x^2))).
%F A367713 a(n) = 1 + Sum_{k=0..n-1} a(floor(k/2)) * a(n-1-k).
%o A367713 (PARI) a_vector(n) = my(v=vector(n+1)); for(i=0, n, v[i+1]=1+sum(j=0, i-1, v[j\2+1]*v[i-j])); v;
%Y A367713 Cf. A367714, A367715.
%Y A367713 Cf. A351972, A367655.
%K A367713 nonn
%O A367713 0,2
%A A367713 _Seiichi Manyama_, Nov 28 2023