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A305091
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Number of nX2 0..1 arrays with every element unequal to 1, 2, 4, 6 or 7 king-move adjacent elements, with upper left element zero.
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2
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1, 3, 9, 10, 27, 109, 168, 349, 1229, 2490, 4767, 14401, 33504, 66377, 175249, 433386, 909235, 2208549, 5522840, 12201285, 28458341, 70294586, 161026423, 370622297, 898784848, 2102285073, 4841334921, 11557476010, 27287134763, 63194732573
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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) = a(n-1) +a(n-2) +8*a(n-3) -16*a(n-5) for n>6
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EXAMPLE
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Some solutions for n=5
..0..1. .0..0. .0..1. .0..1. .0..1. .0..1. .0..1. .0..1. .0..1. .0..1
..1..0. .1..1. .1..0. .0..1. .1..0. .0..1. .0..1. .0..1. .0..1. .1..0
..0..0. .1..1. .1..1. .1..1. .0..0. .1..1. .0..0. .0..0. .0..0. .0..0
..1..0. .1..0. .1..0. .0..1. .0..0. .1..0. .0..1. .1..0. .0..1. .0..1
..0..1. .0..1. .0..1. .0..1. .1..1. .0..1. .0..1. .0..1. .1..0. .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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