A203590 v(n+1)/v(n), where v=A203589.

10, 884, 214600, 101696400, 79516330400, 92782304200000, 151115361757776000, 327547876406050976000, 911669878205463707200000, 3169019350028190185654400000, 13454908637914924371884576000000

Offset: 1

Author

Clark Kimberling, Jan 04 2012

Keywords

• nonn

Comments

See A093883 for a discussion and guide to related sequences.

Programs

Mathematica

f[j_] := 2 j - 1; z = 12;
v[n_] := Product[Product[f[j]^2 + f[k]^2, {j, 1, k - 1}], {k, 2, n}]
Table[v[n], {n, 1, z}]          (* A203589 *)
Table[v[n + 1]/v[n], {n, 1, z}] (* A203590 *)
Table[Product[(2*k - 1)^2 + (2*n + 1)^2, {k, 1, n}], {n, 1, 15}] (* Vaclav Kotesovec, Sep 08 2023 *)

Formula

a(n) ~ 2^(3*n) * n^(2*n) / exp((2 - Pi/2)*n - Pi/4). - Vaclav Kotesovec, Sep 08 2023