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 A072761 #10 May 26 2012 14:52:18 %S A072761 0,1,7,2,5,8,8,3,11,5,9,9,8,9,9,4,9,12,14,7,7,11,12,10 %N A072761 Erroneous version of A127885. %D A072761 M. J. Halm, Sequences (Re)discovered, Mpossibilities 81 (Aug. 2002), p. 1. %H A072761 <a href="/index/3#3x1">Index entries for sequences related to 3x+1 (or Collatz) problem</a> %Y A072761 Cf. A127885, A008577. %K A072761 dead %O A072761 1,3 %A A072761 _N. J. A. Sloane_, May 26 2012