%I #2 Mar 30 2012 18:39:28
%S 1,1,1,3,3,3,3,5,5,5,7,7,9,9,9,9,11,11,13,13,13,15,15,17,17,17,17,19,
%T 19,19,21,21,21,21,23,23,25,25,27,27,27,27,27,29,29,31,31,31,31,31,33,
%U 33,35,35,37,37,37,37,39,39,39,41,41,41,43,43,43,43,45,45,45,47,47,49,49
%N a(n)=A156253(2n)-A156251(2n)
%C a(n) is odd.
%F a(n) is expected to be asymptotic to 2n/3.
%K nonn
%O 1,4
%A _Benoit Cloitre_, Feb 14 2009