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A183436
Number of n X 3 binary arrays with every 1 having exactly one king-move neighbor equal to 1.
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
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
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 04 2011
STATUS
approved