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 A030617 #4 Mar 30 2012 18:56:19 %S A030617 1,1,1,1,2,2,2,3,3,3,3,3,4,4,5,5,5,5,5,4,3,4,3,3,3,4,4,4,4,4,4,4,4,4, %T A030617 4,4,4,5,6,6,6,7,8,8,8,8,8,8,9,9,8,8,8,9,10,10,10,11,11,11,11,10,10, %U A030617 10,11,11,11,11,11,11,11,10,10,9,10,10,10,10,10 %N A030617 a(n)=(# 1's)-(# 0's) in first n terms of A030604. %K A030617 nonn %O A030617 1,5 %A A030617 _Clark Kimberling_