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A231657
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Number of nX2 0..2 arrays with no element less than a strict majority of its horizontal, vertical and antidiagonal neighbors
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1
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3, 15, 93, 458, 2163, 10789, 53813, 265397, 1311447, 6493700, 32130833, 158937397, 786355013, 3890673454, 19249161646, 95235762295, 471186213619, 2331226488364, 11533889645847, 57064690337149, 282331462742945, 1396854097460108
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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) = 9*a(n-1) -28*a(n-2) +65*a(n-3) -167*a(n-4) +235*a(n-5) -237*a(n-6) +327*a(n-7) -345*a(n-8) +267*a(n-9) -198*a(n-10) +193*a(n-11) -88*a(n-12) +52*a(n-13) -20*a(n-14) +16*a(n-15)
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EXAMPLE
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Some solutions for n=7
..2..0....1..0....0..0....0..2....0..0....1..1....0..0....0..0....0..0....2..2
..0..0....0..0....2..0....0..0....1..0....1..2....0..2....0..0....1..0....2..0
..2..1....0..2....1..0....0..1....2..0....1..2....1..1....0..1....0..1....0..0
..1..1....0..1....0..0....2..2....0..1....1..1....1..1....1..0....0..0....2..0
..2..1....0..0....2..2....2..0....0..0....2..1....2..1....0..0....0..2....0..0
..0..0....0..1....2..0....0..0....0..0....2..1....1..0....0..1....2..1....2..1
..0..0....0..0....0..0....2..0....2..2....2..1....0..0....1..2....1..1....2..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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