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A250884
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Number of (7+1)X(n+1) 0..3 arrays with nondecreasing x(i,j)-x(i,j-1) in the i direction and nondecreasing x(i,j)+x(i-1,j) in the j direction
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0
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640002, 2304492, 5640102, 11227928, 19649066, 31484612, 47315662, 67723312, 93288658, 124592796, 162216822, 206741832, 258748922, 318819188, 387533726, 465473632, 553220002, 651353932, 760456518, 881108856, 1013892042, 1159387172
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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) = (290548/3)*n^3 + 254464*n^2 + (669458/3)*n + 65536
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EXAMPLE
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Some solutions for n=1
..0..0....0..0....0..0....0..0....0..0....0..0....0..0....0..0....0..0....0..0
..2..2....1..2....2..2....0..0....1..1....2..2....2..2....1..1....1..1....0..0
..1..2....0..1....3..3....1..1....2..2....1..1....0..0....1..1....0..1....1..1
..0..1....2..3....2..2....1..1....1..1....2..2....1..1....2..2....1..2....2..2
..1..2....0..1....1..1....0..0....3..3....2..2....2..2....2..2....0..2....1..1
..0..1....1..2....3..3....1..1....3..3....3..3....0..1....1..1....0..2....0..1
..1..3....2..3....1..1....2..2....0..0....1..1....1..3....0..0....0..2....0..1
..0..3....0..2....1..1....1..3....0..3....0..3....0..2....3..3....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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