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A250669
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Number of (n+1)X(1+1) 0..3 arrays with nondecreasing x(i,j)+x(i,j-1) in the i direction and nondecreasing absolute value of x(i,j)-x(i-1,j) in the j direction
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3
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104, 520, 2512, 11736, 53032, 233300, 1005121, 4260728, 17835379, 73930174, 304111433, 1243471948, 5060483311, 20518170938, 82950532885, 334582615528, 1347111707003, 5416107760342, 21751360774177, 87278063198468
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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) = 16*a(n-1) -106*a(n-2) +376*a(n-3) -769*a(n-4) +904*a(n-5) -564*a(n-6) +144*a(n-7) for n>11
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EXAMPLE
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Some solutions for n=4
..2..1....2..0....0..2....2..0....0..0....0..0....1..1....1..0....2..1....0..1
..0..3....1..2....1..1....1..1....0..2....0..1....0..2....0..1....0..3....0..3
..2..1....1..2....1..1....0..2....1..1....1..3....1..3....0..1....0..3....0..3
..3..0....2..1....2..2....0..2....2..2....2..2....2..2....0..3....3..0....2..1
..0..3....2..2....1..3....1..1....3..1....2..3....2..2....2..1....0..3....1..3
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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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