A228753 Number of nX7 binary arrays with top left element equal to 1 and no two ones adjacent horizontally or antidiagonally.

13, 289, 6277, 134440, 2876170, 61534448, 1316714732, 28177227352, 602998827928, 12904414518912, 276160275058160, 5909958226524512, 126475877308730464, 2706643227463513344, 57923438257867988416, 1239588830689830585216

Offset

1,1

Comments

Column 7 of A228754

Links

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

Formula

Empirical: a(n) = 34*a(n-1) -324*a(n-2) +1264*a(n-3) -2236*a(n-4) +1816*a(n-5) -624*a(n-6) +64*a(n-7) for n>9

Example

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

Crossrefs

Sequence in context: A278628 A035017 A064750 * A249864 A246462 A375174

Adjacent sequences: A228750 A228751 A228752 * A228754 A228755 A228756

Keyword

nonn

Author

R. H. Hardin Sep 02 2013

Status

approved