A301901 Number of n X n 0..1 arrays with every element equal to 0, 2 or 3 horizontally or antidiagonally adjacent elements, with upper left element zero.

1, 1, 3, 5, 12, 532, 8781, 952467, 81388360, 24626668920, 14235727386501, 14622615341736656, 38187293105036003115, 169994743921070851334774, 1720618701132822565695718755

Offset: 1

Author

R. H. Hardin, Mar 28 2018

Keywords

• nonn

Comments

Diagonal of A301906.

Examples

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

Crossrefs

Cf. A301906.