A183436 Number of n X 3 binary arrays with every 1 having exactly one king-move neighbor equal to 1.

3, 13, 29, 89, 273, 751, 2221, 6485, 18647, 54395, 157947, 457879, 1330821, 3863375, 11214839, 32568969, 94558013, 274542857, 797165417, 2314532695, 6720246173, 19512370773, 56654003695, 164495136155, 477612471027, 1386747980543

Offset

1,1

Comments

Column 3 of A183442.

Links

R. H. Hardin, Table of n, a(n) for n = 1..200

Formula

Empirical: a(n) = a(n-1) + 3*a(n-2) + 8*a(n-3) - a(n-4) - 2*a(n-5) - 2*a(n-6).

Empirical g.f.: x*(3 + 10*x + 7*x^2 - 3*x^3 - 4*x^4 - 2*x^5) / (1 - x - 3*x^2 - 8*x^3 + x^4 + 2*x^5 + 2*x^6). - Colin Barker, Mar 29 2018

Example

Some solutions for 5 X 3.
..0..0..0....0..1..0....0..0..1....1..0..0....1..0..0....0..0..0....1..0..0
..0..1..0....0..1..0....0..1..0....1..0..0....1..0..1....0..0..0....1..0..0
..1..0..0....0..0..0....0..0..0....0..0..0....0..0..1....0..1..1....0..0..0
..0..0..1....0..0..0....0..0..1....0..0..1....0..0..0....0..0..0....1..0..0
..0..0..1....0..1..1....0..0..1....0..1..0....0..0..0....1..1..0....0..1..0

Crossrefs

Cf. A183442.

Sequence in context: A227541 A023553 A268184 * A154300 A051805 A352267

Adjacent sequences: A183433 A183434 A183435 * A183437 A183438 A183439

Keyword

nonn

Author

R. H. Hardin, Jan 04 2011

Status

approved