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A202866
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Number of 4 X 4 0..n arrays with row and column sums one greater than the previous row and column.
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0
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2, 1346, 41852, 491892, 3436102, 17232446, 68544440, 229551288, 672922218, 1773763178, 4286374004, 9634559948, 20367690798, 40850961478, 78277647728, 144113836976, 256112415570, 441063276882, 738481048172, 1205470385252
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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) = (2789/37800)*n^10 + (2789/3780)*n^9 + (6673/2520)*n^8 + (73/21)*n^7 - (1673/1800)*n^6 - (929/180)*n^5 - (14359/7560)*n^4 + (521/189)*n^3 + (3487/3150)*n^2 - (17/21)*n.
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EXAMPLE
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Some solutions for n=3
..0..2..0..3....0..1..0..2....2..0..2..2....0..0..1..3....0..0..1..3
..0..2..1..3....0..1..0..3....0..3..1..3....0..2..3..0....1..2..1..1
..2..0..3..2....1..1..3..0....2..1..3..2....1..0..2..3....2..0..2..2
..3..2..3..0....2..1..2..1....2..3..2..2....3..3..0..1....1..3..2..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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