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A282785
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Number of n X 2 0..1 arrays with no 1 equal to more than one of its king-move neighbors, with the exception of exactly one element.
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1
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0, 0, 8, 16, 72, 240, 736, 2352, 7128, 21424, 63768, 187424, 547136, 1586016, 4570280, 13105488, 37414632, 106404944, 301580704, 852159120, 2401326712, 6750087408, 18931901880, 52989773184, 148039566336, 412873929408, 1149659579720
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OFFSET
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1,3
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LINKS
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FORMULA
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Empirical: a(n) = 2*a(n-1) + 5*a(n-2) +2*a(n-3) - 17*a(n-4) - 24*a(n-5) - 16*a(n-6).
Empirical g.f.: 8*x^3 / (1 - x - 3*x^2 - 4*x^3)^2. - Colin Barker, Feb 21 2019
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EXAMPLE
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Some solutions for n=4:
..0..1. .1..0. .0..0. .0..0. .0..0. .0..0. .1..0. .1..0. .0..0. .0..1
..1..0. .0..1. .1..0. .0..1. .0..1. .1..0. .1..0. .0..1. .1..0. .1..0
..1..0. .1..0. .0..1. .1..0. .1..0. .1..0. .1..0. .0..1. .0..1. .0..1
..0..0. .0..0. .0..1. .1..0. .0..1. .1..0. .0..0. .0..0. .1..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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