Half the number of (n+1)X6 0..3 arrays with every 2X2 subblock having exactly one duplicate clockwise edge difference.

A209784

Half the number of (n+1)X6 0..3 arrays with every 2X2 subblock having exactly one duplicate clockwise edge difference.

Terms

    a(0) =397734a(1) =122871278a(2) =36572974507

External references