A282880 Number of nX3 0..1 arrays with no 1 equal to more than one of its horizontal, vertical and antidiagonal neighbors, with the exception of exactly one element.

1, 8, 74, 430, 2426, 13062, 67676, 342972, 1707597, 8384136, 40716024, 195950228, 935955604, 4442192472, 20968437076, 98509310972, 460879910601, 2148369624844, 9981992555058, 46244594782978, 213681269956154, 985012878231418

Offset: 1

Author

R. H. Hardin, Feb 24 2017

Keywords

• nonn

Comments

Column 3 of A282885.

Examples

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

Links

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

Crossrefs

Cf. A282885.

Formula

Empirical: a(n) = 2*a(n-1) +17*a(n-2) +22*a(n-3) -75*a(n-4) -376*a(n-5) -834*a(n-6) -1206*a(n-7) -1229*a(n-8) -824*a(n-9) -187*a(n-10) +346*a(n-11) +511*a(n-12) +344*a(n-13) +91*a(n-14) -74*a(n-15) -106*a(n-16) -42*a(n-17) +2*a(n-18) +16*a(n-19) +4*a(n-20) -a(n-22)