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 A135904 #2 Mar 30 2012 18:37:08 %S A135904 1,2,8,47,356,3252,34448,412546,5488222,80066096,1268400628, %T A135904 21651578958,395749634342,7705289481276,159106051976460, %U A135904 3471184678351602,79751883928130922,1924103020594546192,48622055377338993264 %N A135904 Column 1 of triangle A135902. %Y A135904 Cf. A135902; A135903, A135905. %K A135904 nonn %O A135904 0,2 %A A135904 _Paul D. Hanna_, Dec 18 2007