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A297297
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Number of nX6 0..1 arrays with every 1 horizontally or antidiagonally adjacent to 2 neighboring 1s.
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2
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1, 6, 17, 50, 157, 495, 1574, 5031, 16123, 51749, 166241, 534301, 1717724, 5523165, 17760715, 57115518, 183679098, 590706934, 1899713778, 6109510235, 19648337645, 63189642502, 203219959503, 653562362810, 2101879559822, 6759719676624
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OFFSET
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1,2
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COMMENTS
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LINKS
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FORMULA
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Empirical: a(n) = 4*a(n-1) -8*a(n-3) -2*a(n-4) +4*a(n-5) +4*a(n-6) +a(n-7) -a(n-8)
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EXAMPLE
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Some solutions for n=5
..0..0..1..1..1..1. .0..1..1..0..0..0. .0..1..1..0..0..0. .0..0..0..0..0..0
..0..1..0..0..1..1. .1..1..0..0..0..0. .1..1..0..1..1..1. .0..0..1..1..1..1
..1..1..1..0..1..1. .0..0..0..1..1..1. .0..0..1..0..1..1. .0..1..0..0..1..1
..0..1..0..0..1..0. .0..0..1..0..1..0. .0..1..0..0..1..0. .1..1..1..0..1..0
..1..1..1..1..0..0. .0..1..1..1..0..0. .1..1..1..1..0..0. .0..1..1..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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