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 A385982 #8 Jul 14 2025 10:01:10
%S A385982 1,1,13,856,195525,124248221,188647130983,611439299390984,
%T A385982 3879035706651051809,44966039381652540837592,
%U A385982 900671755790709615794856671,29761825253146859538914816137428,1560353636451919718380582807368070417,125541398272463750591414559674298911706684
%N A385982 a(0) = 1; a(n) = Sum_{k=0..n-1} (k+1) * binomial(k+5,5) * binomial(n-1,k) * a(k) * a(n-1-k).
%F A385982 E.g.f. A(x) satisfies A(x) = exp( Sum_{k=0..5} binomial(5,k) * x^(k+1)/k! * (d^k/dx^k A(x)) ), where (d^0/dx^0 A(x)) = A(x) by convention.
%o A385982 (PARI) a_vector(n) = my(v=vector(n+1)); v[1]=1; for(i=1, n, v[i+1]=sum(j=0, i-1, (j+1)*binomial(j+5, 5)*binomial(i-1, j)*v[j+1]*v[i-j])); v;
%Y A385982 Cf. A000272, A156326, A385979, A385980, A385981.
%K A385982 nonn
%O A385982 0,3
%A A385982 _Seiichi Manyama_, Jul 14 2025