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A224189
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Number of nX7 0..2 arrays with rows unimodal and columns nondecreasing
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1
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239, 9503, 165212, 1727738, 12741432, 72710554, 340780382, 1366188661, 4823267213, 15322738603, 44529268480, 119909493132, 302279622352, 719306742780, 1626780581324, 3516536949577, 7300336446323, 14614022023815
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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) = (118519/21794572800)*n^14 + (93527/444787200)*n^13 + (6343/1710720)*n^12 + (9456619/239500800)*n^11 + (1028647/3628800)*n^10 + (10525213/7257600)*n^9 + (5190079/952560)*n^8 + (47462621/3110400)*n^7 + (99470417/3110400)*n^6 + (542507339/10886400)*n^5 + (226284461/3991680)*n^4 + (453542611/9979200)*n^3 + (60780847/2522520)*n^2 + (96119/12870)*n + 1
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EXAMPLE
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Some solutions for n=3
..0..0..0..0..1..0..0....0..0..1..2..0..0..0....0..0..1..1..2..0..0
..0..1..1..2..1..1..0....0..0..1..2..1..0..0....0..2..2..2..2..1..1
..0..2..2..2..2..1..0....0..0..1..2..1..1..1....2..2..2..2..2..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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