A203680 v(n+1)/v(n), where v=A203679.

7, 588, 686784, 11999490048, 3246966011068416, 13834880585785015271424, 935753249231126352597092401152, 1008697565620854720371433477717910093824, 17363204603463390874081663579386879116150726197248

Offset

1,1

Comments

See A093883 for a discussion and guide to related sequences.

Links

Table of n, a(n) for n=1..9.

Mathematica

f[j_] := 2^(j - 1); z = 12;
u[n_] := Product[f[j]^2 + f[j] f[k] + f[k]^2, {j, 1, k - 1}]
v[n_] := Product[u[n], {k, 2, n}]
Table[v[n], {n, 1, z}]          (* A203679 *)
Table[v[n + 1]/v[n], {n, 1, z}] (* A203680 *)

Crossrefs

Sequence in context: A080810 A153405 A322899 * A261532 A295814 A087772

Adjacent sequences: A203677 A203678 A203679 * A203681 A203682 A203683

Keyword

nonn

Author

Clark Kimberling, Jan 04 2012

Status

approved