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 A047124 #4 Mar 30 2012 18:56:53 %S A047124 1,1,6,22,86,335,1307,5071,19664,76299,296396,1152682,4487818, %T A047124 17492162,68252789,266589233,1042279572,4078677195,15974343417, %U A047124 62614027433,245608306154,964087953123,3786809126547,14883181075527 %N A047124 T(n,n-2), array T as in A047120. %K A047124 nonn %O A047124 2,3 %A A047124 _Clark Kimberling_