A268736 Number of nX4 binary arrays with some 1 horizontally or vertically adjacent to some other 1 exactly once.

5, 48, 396, 2876, 19591, 128232, 816009, 5087814, 31228804, 189328186, 1136393919, 6764778660, 39991075367, 235019630164, 1374139675314, 7998875575940, 46380134987289, 267999333435856, 1543818690094499, 8868640131544198

Offset: 1

Author

R. H. Hardin, Feb 12 2016

Keywords

• nonn

Comments

Column 4 of A268740.

Examples

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

Links

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

Crossrefs

Cf. A268740.

Formula

Empirical: a(n) = 8*a(n-1) +2*a(n-2) -82*a(n-3) -49*a(n-4) +124*a(n-5) +39*a(n-6) -58*a(n-7) -6*a(n-8) +8*a(n-9) -a(n-10)