A203514 Vandermonde sequence using x^2 + xy + y^2 applied to (1,3,5,...,2n-1).

1, 13, 19747, 9692360769, 3007399210929125649, 974293562642242789006882422237, 492054106680311213790793284550789224583937187, 540918035328864126384298694506545526610971072745364246025968225

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[j] f[k] + f[k]^2,
{j, 1, k - 1}], {k, 2, n}]
Table[v[n], {n, 1, z}]          (* A203514 *)
Table[v[n + 1]/v[n], {n, 1, z}] (* A203515 *)