A183820 1/256 the number of (n+1)X(n+1) 0..3 arrays with no 2X2 subblock being a reflection across the shared element pair of any horizontal or vertical neighbor.

1, 813, 8538066, 1163575148283, 2051388696859571241

Offset: 1

Author

R. H. Hardin Jan 07 2011

Keywords

• nonn

Comments

Diagonal of A183827

Examples

			Some solutions with upper left block zero for 3X3
..0..0..1....0..0..3....0..0..1....0..0..0....0..0..3....0..0..1....0..0..3
..0..0..0....0..0..3....0..0..0....0..0..3....0..0..2....0..0..3....0..0..3
..1..1..3....2..1..1....0..2..1....2..1..0....2..2..2....0..2..1....1..3..1