%I #5 Mar 30 2012 18:39:17
%S 1,1,0,3,2,1,4,1,6,3,4,3,6,1,12,9,2,13,8,3,14,7,8,7,10,5,16,5,18,7,16,
%T 1,30,27,20,5,26,15,8,23,6,29,16,11,22,1,44,41,34,19,12,27,2,49,44,33,
%U 10,37,16,27,6,49,36,9,46,27,12,43,18,33,4,63,54,35,4,67,58,39,0,79,78,75
%N a(0)=1, a(n)=abs(n-2*a(n-1)).
%C a(n)=0 for n=2,78,234,430,1502,2942,6058,6618,18910,54222...
%K nonn
%O 0,4
%A _Benoit Cloitre_, Apr 12 2003