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 A026576 #4 Mar 30 2012 18:56:09 %S A026576 1,3,18,65,346,1288,6818,25518,136152,510532,2745347,10309234, %T A026576 55784794,209766714,1140670242,4294635438,23445204441 %N A026576 T(2n,n-2), T given by A026568. %K A026576 nonn %O A026576 2,2 %A A026576 _Clark Kimberling_