1/16 the number of (n+1) X 2 0..7 arrays with every 2 X 2 subblock strictly increasing clockwise or counterclockwise with one decrease, and at least two adjacent blocks having the same increasing direction.

A183730

1/16 the number of (n+1) X 2 0..7 arrays with every 2 X 2 subblock strictly increasing clockwise or counterclockwise with one decrease, and at least two adjacent blocks having the same increasing direction.

Terms

    a(0) =0a(1) =21a(2) =563a(3) =9403a(4) =135578a(5) =1814815a(6) =23204876a(7) =287769879a(8) =3491293862a(9) =41667398364a(10) =490998416023

External references