318669domain: NAppears in sequencesa(n) = a(n-1) + a(n-2) + a([(n-1)/2]), where a(0) = 1, a(1) = 1, a(2) = 1.at n=26A298352Number of nX4 0..1 arrays with every element unequal to 1, 2, 4, 6, 7 or 8 king-move adjacent elements, with upper left element zero.at n=15A316753