A202798 Number of nX4 binary arrays with every one adjacent to another one horizontally or vertically.

7, 126, 1718, 22946, 311144, 4217066, 57127796, 773948962, 10485233258, 142050385280, 1924452482144, 26071860295098, 353213105139604, 4785216541174944, 64828561353680056, 878276318748587482

Offset: 1

Author

R. H. Hardin Dec 24 2011

Keywords

• nonn

Comments

Column 4 of A202802

Examples

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

Links

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

Formula

Empirical: a(n) = 13*a(n-1) -7*a(n-2) +181*a(n-3) +123*a(n-4) +940*a(n-5) +545*a(n-6) -2084*a(n-7) -1964*a(n-8) +1512*a(n-9) +1984*a(n-10) -512*a(n-11) -1024*a(n-12)