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A305335
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Number of nX3 0..1 arrays with every element unequal to 0, 1, 2, 5 or 8 king-move adjacent elements, with upper left element zero.
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1
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4, 5, 12, 26, 62, 166, 431, 1091, 2812, 7268, 18741, 48294, 124560, 321313, 828693, 2137285, 5512541, 14218105, 36671374, 94583059, 243949927, 629198761, 1622836684, 4185639740, 10795653340, 27844280385, 71816305058, 185229485865
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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) +3*a(n-2) +3*a(n-3) +2*a(n-4) -3*a(n-5) -8*a(n-6) -4*a(n-7) for n>8
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EXAMPLE
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Some solutions for n=5
..0..0..0. .0..1..0. .0..1..0. .0..1..0. .0..1..0. .0..1..0. .0..0..0
..0..0..0. .0..0..0. .0..0..0. .0..0..0. .0..0..0. .0..0..0. .0..0..0
..0..1..0. .1..0..0. .1..0..0. .0..0..1. .0..0..0. .0..0..0. .1..0..0
..0..0..0. .0..0..0. .0..0..1. .0..0..0. .0..0..0. .0..0..0. .0..0..0
..0..0..0. .0..1..0. .0..0..0. .0..1..0. .0..0..0. .0..1..0. .0..1..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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