%I

%S 1,2,5,6,13,14,25,30,49,50,97,98,165,186,325,326,621,622,1161,1230,

%T 2257,2258,4481,4498,8597,8858,17125,17126,34077,34078,66985,68014,

%U 133553,133634,267057,267058,529205,533306,1058261,1058262,2115133

%N Expansion of (1/(1-x))*sum(k>=2,x^k/(1-2x^k)).

%F a(n)=sum{k=0..floor(n/2), floor((n-k+1)/(k+1))*2^k}.

%Y Cf. A002541.

%K easy,nonn

%O 0,2

%A _Paul Barry_, Oct 19 2005