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 A225366 #20 Sep 13 2013 21:26:11 %S A225366 0,2,5,6,6,13,20,13,20,19,23,41 %N A225366 Grundy value of an n X n rectangle in the game of Chomp. %D A225366 E. R. Berlekamp, J. H. Conway and R. K. Guy, Winning Ways vol. 2, 598-600. %H A225366 A. E. Brouwer, <a href="http://www.win.tue.nl/~aeb/games/chomp.html">Chomp</a> %K A225366 nonn,more %O A225366 1,2 %A A225366 _Patrick Devlin_, May 06 2013