A203525 a(n) = v(n+1)/(8*v(n)), where v=A203524.

1, 15, 504, 17280, 1108800, 59304960, 5613753600, 944393748480, 83547459072000, 18057977118720000, 2985679725841612800, 366843845931171840000, 71218197373471948800000, 22048551163610844364800000, 7384118713322835982417920000

Offset: 1

Author

Clark Kimberling, Jan 03 2012

Keywords

• nonn
• easy

Comments

See A093883 for a discussion and guide to related sequences.

Crossrefs

Cf. A000040, A093883, A203315, A203524, A203526.

Programs

Mathematica

f[j_] := Prime[j + 1]; z = 17;
v[n_] := Product[Product[f[k] + f[j], {j, 1, k - 1}], {k, 2, n}]
d[n_] := Product[(i - 1)!, {i, 1, n}]    (* A000178 *)
Table[v[n], {n, 1, z}]                   (* A203524 *)
Table[v[n + 1]/(8 v[n]), {n, 1, z - 1}]  (* A203525 *)
Table[v[n]/d[n], {n, 1, 20}]             (* A203526 *)

Extensions

Definition corrected by Georg Fischer, Nov 26 2021