33983domain: NAppears in sequencesa(n) = numerator of Sum_{k>=1} floor(n/k)/2^k.at n=12A178965Triangle T(n,k), n >= 2, 0 <= k <= floor(n^2/2)-n, read by rows, where T(n,k) is the number of 2*(k+n)-cycles in the n X n grid graph which pass through NW and SW corners.at n=34A333652