A207849 Number of 6Xn 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 0 0 and 1 1 1 vertically

26, 676, 2080, 9672, 41444, 181896, 794768, 3479268, 15223104, 66632488, 291591092, 1276262520, 5585326656, 24445752916, 106984774208, 468241205640, 2049246237012, 8968858409576, 39252328435216, 171793006303620

Offset

1,1

Comments

Row 6 of A207845

Links

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

Formula

Empirical: a(n) = 3*a(n-1) +17*a(n-2) -45*a(n-3) -47*a(n-4) +155*a(n-5) -155*a(n-7) +47*a(n-8) +45*a(n-9) -17*a(n-10) -3*a(n-11) +a(n-12) for n>13

Example

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

Crossrefs

Sequence in context: A208377 A208067 A207932 * A208838 A208686 A207350

Adjacent sequences: A207846 A207847 A207848 * A207850 A207851 A207852

Keyword

nonn

Author

R. H. Hardin Feb 21 2012

Status

approved