A268767 Number of n X n 0..2 arrays with some element plus some horizontally, vertically, diagonally or antidiagonally adjacent neighbor totalling two exactly once.

0, 12, 112, 2296, 64112, 3104544, 255353744, 36091542548, 8990276037592, 3911658481295924, 3022669494445395808, 4128305052223833006600, 10045914708457218016317000, 43496963453603913793217952196

Offset: 1

Author

R. H. Hardin, Feb 13 2016

Keywords

• nonn

Comments

Diagonal of A268774.

Examples

			Some solutions for n=4
..0..1..0..0. .1..2..2..2. .2..2..2..2. .0..1..0..0. .1..0..0..0
..0..0..1..0. .1..2..2..2. .2..2..2..2. .1..0..0..0. .0..0..1..0
..0..0..0..0. .2..2..2..2. .2..2..2..1. .0..0..0..0. .1..0..0..0
..0..1..0..0. .2..1..2..2. .2..2..2..1. .1..0..1..0. .1..0..0..1
		

Links

• R. H. Hardin, Table of n, a(n) for n = 1..17

Crossrefs

Cf. A268774.