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 A203766 #7 Jan 14 2013 07:52:05
%S A203766 1,2,50,10000,169000000,51409800000000,3714358050000000000000,
%T A203766 8587595811600000000000000000000,
%U A203766 9487238856297219731001600000000000000000000,524056459404241401975165324773422080000000000000000000000
%N A203766 Vandermonde sequence using x^2 + y^2 applied to (1,1,2,2,...,floor(n/2)).
%C A203766 See A093883 for a discussion and guide to related sequences.
%t A203766 f[j_] := Floor[(j + 1)/2]; z = 16;
%t A203766 u := Product[f[j]^2 + f[k]^2, {j, 1, k - 1}]
%t A203766 v[n_] := Product[u, {k, 2, n}]
%t A203766 Table[v[n], {n, 1, z}] (* A203766 *)
%t A203766 Table[v[n + 1]/v[n], {n, 1, z}] (* A203767 *)
%K A203766 nonn
%O A203766 1,2
%A A203766 _Clark Kimberling_, Jan 05 2012