A228795 Number of nX7 binary arrays with top left element equal to 1 and no two ones adjacent horizontally or nw-se.

13, 240, 5223, 111966, 2404290, 51557716, 1104367784, 23641626212, 505993241296, 10828817788952, 231743779512528, 4959437834349136, 106134373970906624, 2271325959440419296, 48607446692414050880, 1040222244289865070400

Offset

1,1

Comments

Column 7 of A228796

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>10

Example

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

Crossrefs

Sequence in context: A000824 A229384 A181035 * A271782 A157969 A218229

Adjacent sequences: A228792 A228793 A228794 * A228796 A228797 A228798

Keyword

nonn

Author

R. H. Hardin Sep 04 2013

Status

approved