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A183389
Half the number of n X 5 binary arrays with no element unequal to a strict majority of its king-move neighbors.
1
3, 3, 3, 8, 21, 49, 136, 355, 933, 2502, 6653, 17823, 47798, 128301, 344943, 927972, 2498033, 6728001, 18126410, 48849585, 131672723, 354973646, 957076001, 2580677445, 6959034768, 18766590985, 50610139265, 136490237350, 368107422167
OFFSET
1,1
COMMENTS
Column 5 of A183391.
LINKS
FORMULA
Empirical: a(n) = 2*a(n-1) + 5*a(n-2) - 4*a(n-3) - 11*a(n-4) - 3*a(n-5) + 4*a(n-6) - 8*a(n-7) + 10*a(n-9) - 2*a(n-10) - a(n-11) for n>12.
Empirical g.f.: x*(3 - 3*x - 18*x^2 - x^3 + 35*x^4 + 21*x^5 - 5*x^6 + 31*x^7 + 6*x^8 - 31*x^9 + 3*x^10 + 3*x^11) / (1 - 2*x - 5*x^2 + 4*x^3 + 11*x^4 + 3*x^5 - 4*x^6 + 8*x^7 - 10*x^9 + 2*x^10 + x^11). - Colin Barker, Mar 28 2018
EXAMPLE
Some solutions with a(1,1)=0 for 7 X 5:
..0..0..0..1..1....0..0..0..0..0....0..0..0..0..0....0..0..0..0..0
..0..0..0..1..1....0..0..0..0..0....0..0..0..0..0....0..0..0..0..0
..0..0..0..0..1....0..0..0..0..0....1..1..0..0..0....1..1..1..0..0
..0..0..0..0..1....0..0..0..1..1....1..1..1..1..1....1..1..1..1..1
..0..0..0..1..1....0..0..1..1..1....0..0..1..1..1....0..0..1..1..1
..0..0..0..1..1....1..1..1..1..1....0..0..0..1..1....0..0..0..0..0
..0..0..0..1..1....1..1..1..1..1....0..0..0..1..1....0..0..0..0..0
CROSSREFS
Cf. A183391.
Sequence in context: A241739 A226509 A329694 * A275530 A180637 A362376
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 04 2011
STATUS
approved