A269283 Number of n X n 0..3 arrays with some element plus some horizontally or antidiagonally adjacent neighbor totalling three no more than once.

4, 216, 62748, 87559668, 598478857956, 20680187784811380, 3689070798270477232620, 3444847181845510308844394628, 16998439594375033474993893597991428

Offset: 1

Author

R. H. Hardin, Feb 21 2016

Keywords

• nonn

Comments

Diagonal of A269289.

Examples

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

Links

• R. H. Hardin, Table of n, a(n) for n = 1..11

Crossrefs

Cf. A269289.