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 A203518 #14 Apr 09 2021 03:36:51
%S A203518 1,3,60,20160,259459200,329533940736000,102591687479575117824000,
%T A203518 20251578856869019790329341542400000,
%U A203518 6518596139761671764183992268499872995344384000000,8899914870403074273776879003081000194727401271025610417766400000000
%N A203518 a(n) = Product_{2 <= i < j <= n+1} (F(i) + F(j)), where F = A000045 (Fibonacci numbers).
%C A203518 Each term divides its successor, as in A203519. It is conjectured that each term is divisible by the corresponding superfactorial, A000178(n). See A093883 for a guide to related sequences.
%F A203518 a(n) ~ c * d^n * phi^(n^3/3 + n^2/2) / 5^(n^2/4), where phi = A001622 = (1+sqrt(5))/2 is the golden ratio, d = 3.99077126463315610748163699882855013294148355045548571306491607634698645935... and c = 0.019290318831631524125422284... - _Vaclav Kotesovec_, Apr 09 2021
%p A203518 F:= combinat[fibonacci]:
%p A203518 a:= n-> mul(mul(F(i)+F(j), i=2..j-1), j=3..n+1):
%p A203518 seq(a(n), n=1..12); # _Alois P. Heinz_, Jul 23 2017
%t A203518 f[j_] := Fibonacci[j + 1]; z = 15;
%t A203518 v[n_] := Product[Product[f[k] + f[j], {j, 1, k - 1}], {k, 2, n}]
%t A203518 d[n_] := Product[(i - 1)!, {i, 1, n}] (* A000178 *)
%t A203518 Table[v[n], {n, 1, z}] (* A203518 *)
%t A203518 Table[v[n + 1]/v[n], {n, 1, z - 1}] (* A203519 *)
%t A203518 Table[v[n]/d[n], {n, 1, 20}] (* A203520 *)
%Y A203518 Cf. A000045, A203519.
%K A203518 nonn
%O A203518 1,2
%A A203518 _Clark Kimberling_, Jan 03 2012
%E A203518 Name edited by _Alois P. Heinz_, Jul 23 2017