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A251066
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Number of (2+1)X(n+1) 0..2 arrays with no 2X2 subblock having x11-x00 less than x10-x01
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1
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336, 2740, 17129, 89429, 410718, 1716324, 6678657, 24601591, 86829924, 296316228, 984577369, 3202676417, 10242533906, 32315864964, 100861744449, 312101151267, 959163561400, 2931830099988, 8923446044937, 27069106904461, 81899632621478
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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) = 18*a(n-1) -146*a(n-2) +706*a(n-3) -2268*a(n-4) +5102*a(n-5) -8246*a(n-6) +9654*a(n-7) -8131*a(n-8) +4808*a(n-9) -1896*a(n-10) +448*a(n-11) -48*a(n-12)
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EXAMPLE
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Some solutions for n=4
..2..2..2..1..2....0..0..0..0..0....1..2..2..1..2....0..0..1..1..1
..0..0..0..1..2....0..0..0..2..2....0..0..1..2..1....1..2..1..2..2
..0..1..2..1..0....2..2..2..1..1....2..2..1..0..2....1..0..2..1..2
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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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