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 A385835 #16 Jul 12 2025 21:33:35
%S A385835 1,2,7,51,660,13350,390886,15728919,836469748,56989647229,
%T A385835 4849599126797,504709937298467,63117270187248665,9344222191368190761,
%U A385835 1616899887657388367640,323430766605746093449465,74074314477265886578774322,19261037812212680097678843345,5643873902659784713257894768422
%N A385835 a(n) = 1 + Sum_{k=0..n-1} (1 + k^2) * a(k) * a(n-1-k).
%H A385835 Seiichi Manyama, <a href="/A385835/b385835.txt">Table of n, a(n) for n = 0..253</a>
%F A385835 G.f. A(x) satisfies A(x) = 1/( (1 - x) * ( 1 - x*A(x) - x^2 * (d/dx A(x)) - x^3 * (d^2/dx^2 A(x)) ) ).
%o A385835 (PARI) a_vector(n) = my(v=vector(n+1)); for(i=0, n, v[i+1]=1+sum(j=0, i-1, (1+j^2)*v[j+1]*v[i-j])); v;
%Y A385835 Cf. A321087, A385836, A385837, A385838, A385839.
%Y A385835 Cf. A385758.
%K A385835 nonn
%O A385835 0,2
%A A385835 _Seiichi Manyama_, Jul 09 2025