9225765domain: NAppears in sequencesHalf the number of (n+1) X 4 0..2 arrays with every 2 X 2 subblock having two or four distinct clockwise edge differences.at n=6A209506Half the number of (n+1)X8 0..2 arrays with every 2X2 subblock having two or four distinct clockwise edge differences.at n=2A209510