436593domain: NAppears in sequencesNumber of (n+2)X(1+2) 0..3 arrays with every 3X3 subblock row, column, diagonal and antidiagonal sum not equal to 0 2 3 6 or 7.at n=12A252294Number of free linear midpoint-free polycubes of size n, identifying rotations and reflections.at n=39A368032