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A205209
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Number of (n+1)X3 0..2 arrays with the determinants of 2X2 subblocks nondecreasing rightwards and downwards
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1
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452, 3248, 23578, 203313, 1846145, 17014174, 157776973, 1467364433, 13666197180, 127366953026, 1187443362372, 11072379506700, 103253395267594, 962908489874374, 8979955402839772, 83746661590075524, 781021282761628826
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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) = 15*a(n-1) -49*a(n-2) -97*a(n-3) +664*a(n-4) -980*a(n-5) +448*a(n-6) for n>13
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EXAMPLE
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Some solutions for n=4
..0..0..1....0..0..2....0..1..1....2..1..0....2..0..0....0..0..0....1..2..2
..1..0..0....1..0..2....2..1..1....2..1..0....1..0..0....2..2..0....1..1..1
..1..0..2....0..0..0....0..0..0....2..1..0....2..0..0....0..0..0....0..0..0
..2..0..1....1..2..0....0..2..1....0..0..0....1..0..2....0..2..1....0..1..1
..2..0..1....0..0..0....0..0..2....2..0..2....2..0..2....0..2..1....0..2..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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