A240512 Number of n X n 0..1 arrays with no element equal to exactly two horizontal and vertical neighbors, with new values 0..1 introduced in row major order.

1, 3, 10, 99, 1376, 37624, 1906245, 180760099, 31517059634, 10196460883584

Offset: 1

Author

R. H. Hardin, Apr 06 2014

Keywords

• nonn

Comments

Diagonal of A240519.

Examples

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

Crossrefs

Cf. A240519.