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A317031
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Number of nX3 0..1 arrays with every element unequal to 0, 1, 2, 4, 5, 6 or 8 king-move adjacent elements, with upper left element zero.
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1
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4, 14, 30, 82, 280, 842, 2591, 8141, 25387, 79075, 247002, 771516, 2408705, 7522325, 23494122, 73374104, 229158274, 715707738, 2235297120, 6981287296, 21804026411, 68098596051, 212686440221, 664265316611, 2074643216856, 6479557040796
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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) = 2*a(n-1) +4*a(n-2) +8*a(n-3) -13*a(n-4) -45*a(n-5) -55*a(n-6) +30*a(n-7) +163*a(n-8) +194*a(n-9) +12*a(n-10) -223*a(n-11) -209*a(n-12) -51*a(n-13) +37*a(n-14) +3*a(n-15) for n>17
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EXAMPLE
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Some solutions for n=5
..0..1..0. .0..0..0. .0..1..1. .0..0..0. .0..1..1. .0..1..0. .0..1..0
..0..0..0. .0..0..0. .0..1..1. .0..0..1. .0..1..1. .0..0..1. .0..0..0
..1..0..0. .1..0..0. .0..0..0. .0..0..0. .1..1..1. .0..0..0. .0..0..1
..1..0..0. .1..0..0. .0..0..0. .0..0..0. .1..1..1. .0..0..0. .0..0..1
..0..0..0. .1..1..1. .0..0..0. .0..1..1. .0..0..1. .0..0..0. .0..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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