%I
%S 0,0,0,1,0,0,1,2,0,1,0,2,1,2,2,4,0,0,1,2,0,0,2,3,1,2,2,4,2,3,4,6,0,1,
%T 0,2,1,2,2,4,0,2,0,3,2,4,3,6,1,2,2,4,2,3,4,6,2,4,3,6,4,6,6,9,0,0,1,2,
%U 0,0,2,3,1,2,2,4,2,3,4,6,0,0,2,3,0,0,3,4,2,3,4,6,3,4,6,8,1,2,2
%N Let the binary expansion of n be n = Sum_{k} 2^{r_k}, let e(n) be the number of r_k's that are even, o(n) the number that are odd; sequence gives e(n)*o(n).
%C e(n)+o(n) = A000120(n), the binary weight of n.
%e If n = 43 = 2^0+2^2+2^3+2^5, e(43)=1, o(43)=3.
%o See link in A139351 for Fortran program.
%Y Cf. A000120, A139351A139355, A039004, A139370A139373.
%K nonn
%O 0,8
%A _Nadia Heninger_ and _N. J. A. Sloane_, Jun 07 2008
