A230669 Number of n X n 0..2 arrays x(i,j) with each element horizontally, diagonally or antidiagonally next to at least one element with value 2-x(i,j).

0, 15, 1173, 730503, 4022141121, 169908632412447, 55314799986833459367, 140277459587738407279576815

Offset: 1

Author

R. H. Hardin, Oct 27 2013

Keywords

• nonn

Comments

Diagonal of A230675

Examples

			Some solutions for n=3
..2..2..0....1..1..1....1..2..0....0..1..0....1..1..0....1..1..2....2..0..1
..0..0..0....0..2..2....0..1..0....1..2..1....2..2..0....1..0..0....1..1..1
..2..2..2....2..0..2....0..2..0....0..1..1....0..0..0....0..2..0....2..0..2