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A206311
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Number of (n+1)X2 0..3 arrays with the number of clockwise edge increases in every 2X2 subblock equal to two, and every 2X2 determinant nonzero
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1
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112, 873, 6831, 53463, 418468, 3275406, 25637095, 200665376, 1570637751, 12293615779, 96223962193, 753159288558, 5895089964664, 46141747460483, 361158332020412, 2826840073596765, 22126098426129671, 173184268942327111
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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) = 5*a(n-1) +21*a(n-2) +13*a(n-3) -31*a(n-4) -17*a(n-5) +34*a(n-6) +2*a(n-7) -9*a(n-8) -a(n-9)
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EXAMPLE
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Some solutions for n=4
..2..2....3..0....0..1....3..2....1..1....0..1....3..1....2..0....1..0....2..2
..0..3....2..2....1..3....0..3....3..2....1..2....3..2....1..1....0..1....0..3
..3..0....0..3....2..1....3..0....0..3....0..2....1..3....3..2....1..2....2..1
..0..1....1..0....1..0....1..3....2..0....2..1....3..0....2..1....2..1....1..0
..2..3....2..1....3..1....2..1....0..1....0..3....1..1....3..2....0..2....2..1
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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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