1/729 the number of (n+2) X 8 0..2 arrays with no 3 X 3 subblock trace equal to any horizontal or vertical neighbor 3 X 3 subblock trace.

A185888

1/729 the number of (n+2) X 8 0..2 arrays with no 3 X 3 subblock trace equal to any horizontal or vertical neighbor 3 X 3 subblock trace.