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

A209780

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

Terms

    a(0) =64a(1) =576a(2) =5074a(3) =44948a(4) =397734a(5) =3520628a(6) =31161462a(7) =275819644a(8) =2441352670a(9) =21609092620a(10) =191268034094

External references