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 A203194 #5 Mar 30 2012 18:58:05
%S A203194 1,3,20,412,29080,7344960,6790976640,23310543674880,
%T A203194 300020122552550400,14587151144134593024000,
%U A203194 2695072097623041659787264000,1901191652075515716657381408768000,5141119908014521906432306538772430848000
%N A203194 (n-1)-st elementary symmetric function of the first n terms of (1,2,6,20,70,252,...)=A000984.
%t A203194 f[k_] := Binomial[2 k - 2, k - 1];
%t A203194 t[n_] := Table[f[k], {k, 1, n}]
%t A203194 a[n_] := SymmetricPolynomial[n - 1, t[n]]
%t A203194 Table[a[n], {n, 1, 14}] (* A203194 *)
%Y A203194 Cf. A000984.
%K A203194 nonn
%O A203194 1,2
%A A203194 _Clark Kimberling_, Dec 30 2011