1/81 the number of (n+1) X 4 0..2 arrays with no 2 X 2 subblock being a reflection across the shared element pair of any horizontal or vertical neighbor.

A183814

1/81 the number of (n+1) X 4 0..2 arrays with no 2 X 2 subblock being a reflection across the shared element pair of any horizontal or vertical neighbor.

Terms

    a(0) =64a(1) =3256a(2) =163208a(3) =8231592a(4) =414246824a(5) =20864057480

External references