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A203759 Vandermonde sequence using x^2 + xy + y^2 applied to (1,1,2,2,...,[n/2]).

%I A203759 #7 Jan 14 2013 04:51:22
%S A203759 1,3,147,86436,5273373924,8686528282691532,4111538282327563523497152,
%T A203759 93412216233151136505901971387334656,
%U A203759 1219854711057286573050999646270927427863304749056
%N A203759 Vandermonde sequence using x^2 + xy + y^2 applied to (1,1,2,2,...,[n/2]).
%C A203759 See A093883 for a discussion and guide to related sequences.
%t A203759 f[j_] := Floor[(j + 1)/2]; z = 13;
%t A203759 u := Product[f[j]^2 + f[j] f[k] + f[k]^2, {j, 1, k - 1}]
%t A203759 v[n_] := Product[u, {k, 2, n}]
%t A203759 Table[v[n], {n, 1, z}]          (* A203759 *)
%t A203759 Table[v[n + 1]/v[n], {n, 1, z}] (* A203760 *)
%K A203759 nonn
%O A203759 1,2
%A A203759 _Clark Kimberling_, Jan 05 2012