A206951 Number of n X n 0..2 arrays avoiding the pattern z z+1 z in any row, column or nw-to-se diagonal.

3, 81, 11804, 9803278, 50967712088, 1627105474024831, 314368117565737962789, 368862218847158027158758198

Offset: 1

Author

R. H. Hardin Feb 13 2012

Keywords

• nonn

Comments

Diagonal of A206957

Examples

			Some solutions for n=4
..1..1..1..0....2..1..0..2....2..0..0..1....2..0..1..1....2..0..0..0
..1..2..2..2....1..2..2..1....1..1..0..1....2..1..0..1....0..1..1..0
..0..2..2..2....1..0..1..2....2..2..1..0....1..2..2..2....0..1..1..2
..2..0..0..1....0..0..2..0....2..2..2..0....1..0..0..0....2..2..1..1