1/4 the number of (n+1) X 3 0..3 arrays with every 2 X 2 subblock having one, three or four distinct clockwise edge differences.

A210150

1/4 the number of (n+1) X 3 0..3 arrays with every 2 X 2 subblock having one, three or four distinct clockwise edge differences.

Terms

    a(0) =820a(1) =42689a(2) =2219034a(3) =115368738a(4) =5997955680a(5) =311831135649

External references