A228688 Number of 7Xn binary arrays with no two ones adjacent horizontally, diagonally or antidiagonally.

128, 577, 21305, 176032, 4008817, 44171841, 806190208, 10258304689, 168184756793, 2301665823616, 35784406285057, 508094306671233, 7692715116119040, 111277331056067617, 1662525457133097145

Offset

1,1

Comments

Row 7 of A228683

Links

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

Formula

Empirical: a(n) = 9*a(n-1) +184*a(n-2) -1201*a(n-3) -7155*a(n-4) +46048*a(n-5) +70745*a(n-6) -591673*a(n-7) -154744*a(n-8) +3207657*a(n-9) -715173*a(n-10) -7580648*a(n-11) +3369552*a(n-12) +7114920*a(n-13) -3800952*a(n-14) -1923264*a(n-15) +1083456*a(n-16)

Example

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

Crossrefs

Sequence in context: A223316 A123293 A188864 * A231529 A197708 A198072

Adjacent sequences: A228685 A228686 A228687 * A228689 A228690 A228691

Keyword

nonn

Author

R. H. Hardin Aug 30 2013

Status

approved