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 A158511 #4 May 01 2013 21:06:46 %S A158511 1,-1,0,0,1,-1,0,1,-1,0,1,-1,0,0,0,0,1,-1,0,0,0,0,1,-1,0,0,1,-1,1,-1, %T A158511 0,0,0,1,-1,0,2,-1,-1,0,1,3,-2,-1,-1,0,1,-1,0,0,0,0,2,-1,-1,1,-1,0,1, %U A158511 -1,0,0,0,0,1,4,-2,-1,-1,-1,1,-1,0,0,0,1,-1,0,2,-1,-1,0,1,2,-2,-1,0,0,1,-1,0 %N A158511 a(n) = A158504(n) - n. %K A158511 sign %O A158511 1,37 %A A158511 _Paul Curtz_, Mar 20 2009 %E A158511 Edited by _N. J. A. Sloane_, Apr 07 2009 %E A158511 More terms from _R. J. Mathar_, Apr 16 2009