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 A026577 #4 Mar 30 2012 18:56:09 %S A026577 1,2,8,34,121,606,2155,11306,40717,217666,792351,4280046,15703156, %T A026577 85410872,315180458,1722900242,6385672193,35040356022 %N A026577 T(2n-1,n-1), T given by A026568. %K A026577 nonn %O A026577 1,2 %A A026577 _Clark Kimberling_