A267661 Number of nX2 0..1 arrays with every repeated value in every row unequal to the previous repeated value, and in every column equal to the previous repeated value, and new values introduced in row-major sequential order.

2, 8, 32, 98, 288, 800, 2178, 5832, 15488, 40898, 107648, 282752, 741762, 1944392, 5094432, 13343778, 34944800, 91503392, 239586050, 627288200, 1642332672, 4299797378, 11257201152, 29472035328, 77159275778, 202006392200

Offset: 1

Author

R. H. Hardin, Jan 19 2016

Keywords

• nonn

Comments

Column 2 of A267667.

Examples

			Some solutions for n=8
..0..1....0..1....0..1....0..1....0..0....0..1....0..1....0..0....0..0....0..1
..0..1....1..1....1..0....0..0....1..1....1..0....1..0....1..0....0..1....0..1
..0..1....1..1....0..1....1..0....0..0....0..1....1..0....0..0....1..0....0..1
..0..0....1..0....1..0....0..1....1..1....1..0....1..0....1..0....0..0....1..1
..1..1....1..1....0..0....1..0....1..1....0..1....1..1....0..1....0..0....0..0
..0..1....1..0....1..0....0..0....0..1....0..0....1..0....0..0....0..0....0..1
..0..1....1..1....1..1....0..0....1..1....0..1....0..0....1..1....1..0....0..0
..0..1....1..0....0..0....0..1....1..0....1..1....1..0....0..0....0..0....1..1
		

Links

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

Crossrefs

Cf. A267667.

Formula

Empirical: a(n) = 4*a(n-1) -2*a(n-2) -6*a(n-3) +4*a(n-4) +2*a(n-5) -a(n-6)