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 A386450 #8 Jul 22 2025 09:51:40
%S A386450 1,1,1,1,1,25,3049,1103713,929323297,1563120681841,4730002253928145,
%T A386450 23848669801185169825,188929157434986723256801,
%U A386450 2244856224793842495701519113,38526222340982767558002054899641,925631015719595748793089592291450945,30325523298479173582153602405524578371265
%N A386450 G.f. A(x) satisfies A(x) = 1/(1 - x - x^5*A''''(x)).
%F A386450 a(0) = 1; a(n) = a(n-1) + Sum_{k=0..n-1} (-6*k + 11*k^2 - 6*k^3 + k^4) * a(k) * a(n-1-k).
%o A386450 (PARI) a_vector(n) = my(v=vector(n+1)); v[1]=1; for(i=1, n, v[i+1]=v[i]+sum(j=0, i-1, sum(k=1, 4, stirling(4, k, 1)*j^k)*v[j+1]*v[i-j])); v;
%Y A386450 Cf. A075834, A386448, A386449, A386451.
%Y A386450 Cf. A385764.
%K A386450 nonn
%O A386450 0,6
%A A386450 _Seiichi Manyama_, Jul 22 2025