A303676 Number of n X n 0..1 arrays with every element unequal to 0, 1 or 3 king-move adjacent elements, with upper left element zero.

1, 5, 9, 28, 76, 177, 367, 774, 1684, 3639, 7597, 15617, 32101, 66074, 135096, 274104, 553668, 1116275, 2245277, 4501938, 9000074, 17953486, 35749382, 71056212, 140977366, 279246077, 552333115, 1091040731

Offset: 1

Author

R. H. Hardin, Apr 28 2018

Keywords

• nonn

Comments

Diagonal of A303682.

Examples

			Some solutions for n=5
..0..0..1..1..0. .0..1..1..0..0. .0..0..0..0..1. .0..0..0..1..1
..0..1..1..1..1. .1..1..1..1..0. .0..0..0..0..0. .0..0..0..0..1
..1..1..1..1..1. .1..1..1..1..1. .0..0..0..0..0. .0..0..0..0..0
..1..1..1..1..1. .1..1..1..1..1. .0..0..0..0..0. .0..0..0..0..0
..1..1..1..1..0. .0..1..1..1..1. .1..0..0..0..0. .0..0..0..0..0
		

Crossrefs

Cf. A303682.