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A228757
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Number of 5Xn binary arrays with top left element equal to 1 and no two ones adjacent horizontally or antidiagonally.
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1
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16, 55, 723, 4808, 43862, 342207, 2876170, 23326164, 192379841, 1574217212, 12928573892, 106000461919, 869759215471, 7134075563384, 58525595955046, 480089753747591, 3938341082031018, 32307082900690396, 265023929648410933
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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) +49*a(n-2) +107*a(n-3) -154*a(n-4) -404*a(n-5) +250*a(n-6) +472*a(n-7) -278*a(n-8) -168*a(n-9) +131*a(n-10) -9*a(n-11) -7*a(n-12) +a(n-13)
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EXAMPLE
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Some solutions for n=4
..1..0..1..0....1..0..1..0....1..0..0..0....1..0..0..0....1..0..0..0
..0..0..0..0....1..0..1..0....1..0..0..0....0..0..0..1....0..0..1..0
..1..0..0..1....1..0..0..0....0..0..0..0....1..0..0..0....1..0..0..1
..1..0..0..1....0..0..1..0....0..0..0..0....1..0..1..0....1..0..0..1
..1..0..0..0....1..0..0..0....1..0..0..1....0..0..0..0....0..0..0..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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