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A208503
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Number of 5 X n 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 1 0 and 1 1 1 vertically.
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1
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13, 169, 234, 650, 1794, 4992, 13806, 38376, 106236, 295074, 817362, 2269098, 6288048, 17450550, 48371544, 134210700, 372088314, 1032237882, 2862135666, 7939298016, 22015398366, 61064779464, 169339275612, 469681757298
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OFFSET
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1,1
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COMMENTS
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LINKS
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FORMULA
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Empirical: a(n) = a(n-1) + 6*a(n-2) - 3*a(n-3) for n>5.
Empirical g.f.: 13*x*(1 + 12*x - x^2 - 43*x^3 + 19*x^4) / (1 - x - 6*x^2 + 3*x^3). - Colin Barker, Jul 03 2018
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EXAMPLE
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Some solutions for n=4:
..0..1..1..1....1..1..1..1....1..1..0..0....1..0..1..1....0..1..0..0
..0..1..0..1....0..1..0..1....1..0..1..1....0..1..1..1....1..1..0..1
..1..0..1..0....1..0..1..0....0..1..1..1....1..1..0..0....1..0..1..1
..1..0..1..1....1..0..1..0....0..1..0..0....1..0..1..0....0..1..1..0
..0..1..0..1....0..1..0..1....1..0..1..0....0..1..1..1....0..1..0..0
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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