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A201189
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Number of nX2 0..2 arrays with every row and column running average nondecreasing rightwards and downwards but some diagonal running average having a decrease
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1
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0, 0, 1, 6, 24, 80, 239, 665, 1756, 4459, 10978, 26369, 62066, 143647, 327756, 738794, 1647917, 3642331, 7986246, 17387367, 37618098, 80932917, 173248897, 369190346, 783527077, 1656712522, 3491205863, 7334452733, 15365201271, 32106206735
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OFFSET
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1,4
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COMMENTS
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LINKS
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FORMULA
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Empirical: a(n) = 10*a(n-1) -37*a(n-2) +48*a(n-3) +55*a(n-4) -237*a(n-5) +186*a(n-6) +209*a(n-7) -450*a(n-8) +150*a(n-9) +280*a(n-10) -297*a(n-11) +20*a(n-12) +126*a(n-13) -69*a(n-14) -5*a(n-15) +16*a(n-16) -4*a(n-17)
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EXAMPLE
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Some solutions for n=9
..0..0....0..0....0..0....0..0....0..0....0..0....0..0....0..0....0..0....0..0
..0..0....0..0....0..0....0..0....0..0....0..0....0..0....0..1....0..0....0..0
..0..0....0..1....0..0....0..0....1..1....0..0....2..2....0..1....1..1....0..0
..0..0....0..1....0..2....0..2....1..1....0..2....1..1....2..2....1..2....0..0
..0..1....0..1....1..1....2..2....1..1....0..1....2..2....1..1....1..1....0..0
..1..2....2..2....2..2....2..2....1..1....2..2....1..2....1..2....2..2....0..0
..1..1....1..1....1..1....1..1....1..2....2..2....2..2....1..2....1..1....1..2
..2..2....1..2....2..2....1..1....2..2....1..1....2..2....2..2....1..1....2..2
..1..1....1..1....1..2....2..2....1..1....1..1....2..2....1..2....2..2....1..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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