2383064182domain: NAppears in sequences1/4 the number of (n+1)X3 0..3 arrays with every 2X2 subblock having one or four distinct clockwise edge differences.at n=6A2098521/4 the number of (n+1) X 8 0..3 arrays with every 2 X 2 subblock having one or four distinct clockwise edge differences.at n=1A209857