A183817 1/81 the number of (n+1)X7 0..2 arrays with no 2X2 subblock being a reflection across the shared element pair of any horizontal or vertical neighbor.

32768, 26630220, 20864057480, 16607782066704, 13143529051807800, 10425296660739253420

Offset: 1

Author

R. H. Hardin Jan 07 2011

Keywords

• nonn

Comments

Column 6 of A183819

Examples

			Some solutions with upper left block zero for 3X7
..0..0..0..0..0..2..1....0..0..0..0..2..0..1....0..0..0..0..2..2..0
..0..0..2..2..1..1..1....0..0..1..1..0..0..1....0..0..2..2..2..2..1
..1..0..1..0..2..1..0....2..0..2..0..1..1..0....1..0..2..0..1..1..0