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 A386504 #13 Jul 24 2025 09:31:47
%S A386504 1,1,1,1,1,1,721,3638881,73388931841,4439222967191041,
%T A386504 671254901566891891201,223293614016982999277652481,
%U A386504 148555455012284806644741491166721,183545166980276574090600617506568885761,396856587856894056179855967245699021196188161,1430118352830649099320069857966516939680956145171201
%N A386504 E.g.f. A(x) satisfies A(x) = exp(x + x^6*A'''''(x)).
%F A386504 a(0) = 1; a(n) = a(n-1) + Sum_{k=0..n-1} (1 + k) * (24*k - 50*k^2 + 35*k^3 - 10*k^4 + k^5) * binomial(n-1,k) * a(k) * a(n-1-k).
%F A386504 a(n) == 1 (mod 720). - _Hugo Pfoertner_, Jul 24 2025
%o A386504 (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, (1+j)*sum(k=1, 5, stirling(5, k, 1)*j^k)*binomial(i-1, j)*v[j+1]*v[i-j])); v;
%Y A386504 Cf. A143925, A385066, A386502, A386503.
%Y A386504 Cf. A385923, A386451.
%K A386504 nonn
%O A386504 0,7
%A A386504 _Seiichi Manyama_, Jul 24 2025