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 A105855 #3 Mar 30 2012 18:50:49 %S A105855 1,0,1,1,2,3,-2,0,6,-4,1,8,-4,3,-2,0,14,-4,-10,4,14,-4,-14,4,14,-8,5, %T A105855 -4,0,25,-6,-14,11,-4,-29,1,8,9,17,-14,2,29,-12,-28,3,20,23,-5,-32,11, %U A105855 29,-12,-37,3,20,23,-14,8,-7,0,53,-9,-20,-31,12,46,-9,-32,26,-7,-53,10,29,39,-7 %N A105855 A104647(n+1) - A104647(n). %K A105855 sign %O A105855 0,5 %A A105855 _Reinhard Zumkeller_, Apr 23 2005