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A297689
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Number of nX3 0..1 arrays with every 1 horizontally, diagonally or antidiagonally adjacent to 0, 2 or 4 neighboring 1s.
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1
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5, 26, 95, 415, 1801, 7526, 32173, 137242, 583129, 2484786, 10583683, 45062520, 191933126, 817441956, 3481360348, 14827246426, 63149259874, 268952155501, 1145471423600, 4878575547192, 20777907778014, 88493407078762
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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) -2*a(n-2) +6*a(n-3) -52*a(n-4) +23*a(n-5) -3*a(n-6) +21*a(n-7) -9*a(n-8)
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EXAMPLE
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Some solutions for n=7
..0..0..0. .1..0..0. .0..0..0. .0..0..1. .0..0..0. .0..0..0. .0..0..1
..0..0..0. .1..0..0. .1..0..1. .0..0..1. .0..0..0. .0..0..1. .0..0..0
..0..0..0. .1..0..0. .0..0..1. .0..0..0. .0..0..1. .0..0..1. .1..1..1
..1..0..0. .0..0..0. .0..0..0. .0..1..1. .0..0..1. .0..0..1. .0..1..0
..0..0..1. .0..0..0. .0..0..1. .1..1..0. .0..0..1. .1..0..0. .1..1..1
..0..0..0. .1..1..1. .0..0..0. .0..0..0. .1..0..1. .1..0..0. .0..0..0
..0..0..0. .1..1..1. .0..1..0. .0..0..0. .1..0..1. .1..0..0. .1..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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