This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A203514 #7 Jan 14 2013 10:12:50
%S A203514 1,13,19747,9692360769,3007399210929125649,
%T A203514 974293562642242789006882422237,
%U A203514 492054106680311213790793284550789224583937187,540918035328864126384298694506545526610971072745364246025968225
%N A203514 Vandermonde sequence using x^2 + xy + y^2 applied to (1,3,5,...,2n-1).
%C A203514 See A093883 for a discussion and guide to related sequences.
%t A203514 f[j_] := 2 j - 1; z = 12;
%t A203514 v[n_] := Product[Product[f[j]^2 + f[j] f[k] + f[k]^2,
%t A203514 {j, 1, k - 1}], {k, 2, n}]
%t A203514 Table[v[n], {n, 1, z}] (* A203514 *)
%t A203514 Table[v[n + 1]/v[n], {n, 1, z}] (* A203515 *)
%K A203514 nonn
%O A203514 1,2
%A A203514 _Clark Kimberling_, Jan 04 2012