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

1,1

Comments

Column 2 of A267667.

Links

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

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)

Example

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

Crossrefs

Cf. A267667.

Sequence in context: A212892 A302936 A227971 * A052481 A306292 A067897

Adjacent sequences: A267658 A267659 A267660 * A267662 A267663 A267664

Keyword

nonn

Author

R. H. Hardin, Jan 19 2016

Status

approved