A203765 Square root of A203764(n).

1, 3, 6, 49, 147, 2028, 8112, 159201, 796005, 20342448, 122054688, 3850078401, 26950548807, 1012487793408, 8099902347264, 353293863908769, 3179644775178921, 157973407966483200, 1579734079664832000, 88087149666575064369

Offset

1,2

Links

Table of n, a(n) for n=1..20.

Mathematica

f[j_] := Floor[(j + 1)/2]; z = 16;
u := Product[f[j]^2 - f[j] f[k] + f[k]^2, {j, 1, k - 1}]
v[n_] := Product[u, {k, 2, n}]
Table[v[n], {n, 1, z}]        (* A203763 *)
Table[v[n + 1]/v[n], {n, 1, z}]  (* A203764 *)
Table[Sqrt[v[n + 1]/v[n]], {n, 1, 20}]  (* A203765 *)

Crossrefs

Cf. A093883.

Sequence in context: A197884 A279706 A032322 * A111752 A102931 A056447

Adjacent sequences: A203762 A203763 A203764 * A203766 A203767 A203768

Keyword

nonn

Author

Clark Kimberling, Jan 05 2012

Status

approved