25769803777domain: NAppears in sequencesa(n) = 6*4^n + 1.at n=16A199116a(n) = 3*8^n + 1.at n=11A199494Half the number of (n+1) X 3 0..2 arrays with every 2 X 2 subblock having exactly two distinct clockwise edge differences.at n=21A209530