A268977 Number of 7Xn 0..2 arrays with some element plus some horizontally or antidiagonally adjacent neighbor totalling two not more than once.

2187, 184320, 5598720, 167226768, 4823705520, 137497776840, 3870355944960, 107884943899488, 2981278225929744, 81772049776604472, 2228316762081730176, 60378377050028640600, 1627890867639031100112, 43698886755490031302440

Offset: 1

Author

R. H. Hardin, Feb 16 2016

Keywords

• nonn

Comments

Row 7 of A268971.

Examples

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

Links

• R. H. Hardin, Table of n, a(n) for n = 1..210
• R. H. Hardin, Empirical recurrence of order 54

Crossrefs

Cf. A268971.

Formula

Empirical recurrence of order 54 (see link above)