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A302207
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Number of nX3 0..1 arrays with every element equal to 0, 2 or 3 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.
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1
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1, 11, 16, 47, 147, 386, 1065, 3063, 8624, 24219, 68527, 193946, 547869, 1548531, 4380048, 12385479, 35018011, 99025330, 280031137, 791849343, 2239169200, 6331964803, 17905479095, 50632882698, 143179634869, 404883140379
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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) = 3*a(n-1) -2*a(n-2) +9*a(n-3) -13*a(n-4) +2*a(n-5) -12*a(n-6) +12*a(n-7) -16*a(n-9)
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EXAMPLE
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Some solutions for n=5
..0..0..0. .0..1..1. .0..1..1. .0..1..0. .0..0..1. .0..1..1. .0..0..0
..1..0..1. .0..1..1. .1..1..0. .1..1..1. .0..0..1. .0..1..1. .1..0..1
..1..0..0. .0..1..0. .0..1..0. .0..1..0. .0..0..1. .0..1..1. .1..0..0
..0..0..1. .0..1..1. .1..1..0. .0..1..1. .1..0..1. .0..1..1. .0..0..1
..0..0..1. .1..1..1. .1..1..1. .1..1..1. .0..0..0. .1..1..0. .1..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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