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 A102564 #2 Mar 30 2012 18:59:02 %S A102564 0,0,1,-1,2,0,1,1,4,2,3,3,4,4,5,1,8,6,7,7,8,8,9,5,10,10,11,7,12,8,9,5, %T A102564 16,14,15,15,16,16,17,13,18,18,19,15,20,16,17,13,22,22,23,19,24,20,21, %U A102564 17,26,22,23,19,24,20,21,9,32,30,31,31,32,32,33,29,34,34,35,31,36,32,33,29,38,38,39,35,40,36,37,33,42,38,39,35,40,36 %N A102564 A000120(A078008(n))-A078008(A000120(n)). %C A102564 It would appear that a(2^(n+1))=2^n=A000079(n); a(2^(n+1)-1)+1=A078008(n); a(2^(n+1)+1)+1=2^n-1; a(4n+1)-a(2n+1)=n; a(8n+1)-a(4n+1)=2n. %Y A102564 Cf. A102563, 102565. %K A102564 easy,sign %O A102564 0,5 %A A102564 _Paul Barry_, Jan 14 2005