A295034 Number of n X n 0..1 arrays with each 1 horizontally or vertically adjacent to 1 or 2 1's.

1, 10, 140, 6686, 898493, 355281224, 411280569141, 1377458578461777, 13439667379225204666, 381706479329790703639253, 31542814403404743062254741113, 7585239934805237805543429969496485

Offset: 1

Author

R. H. Hardin, Nov 12 2017

Keywords

• nonn
• more

Examples

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

Crossrefs

Diagonal of A295040.