A202881 Number of n X n 0..2 arrays with every nonzero element less than or equal to some horizontal or vertical neighbor.

1, 35, 5493, 6092872, 56006562037, 4095290003129296, 2365289879500027706428, 10827985400073310953152590562, 392915439811314078675718437985175633, 112991429416970014192131075985467073204579858

Offset: 1

Author

R. H. Hardin, Dec 25 2011

Keywords

• nonn
• more

Examples

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

Crossrefs

Diagonal of A202889.