A269136 Number of n X n 0..3 arrays with some element plus some horizontally, antidiagonally or vertically adjacent neighbor totalling three no more than once.

4, 148, 18556, 8317996, 14197016484, 95884587957284, 2621894498331024092, 294433751149574057834796, 137064853562490916405823252564, 266206369700280385363973380215109284

Offset: 1

Author

R. H. Hardin, Feb 20 2016

Keywords

• nonn

Comments

Diagonal of A269143.

Examples

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

Crossrefs

Cf. A269143.