1578364domain: NAppears in sequencesNumber of (n+1)X(4+1) 0..1 arrays with every 2X2 subblock ne-sw antidiagonal difference unequal to its neighbors horizontally and nw+se diagonal sum unequal to its neighbors vertically.at n=18A253694Number of alternating compositions of n, including twins (x,x).at n=32A344604