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A252974
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Number of nX6 nonnegative integer arrays with upper left 0 and lower right n+6-5 and value increasing by 0 or 1 with every step right or down
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1
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10, 192, 2859, 30802, 248182, 1592348, 8528422, 39423196, 161160206, 593478797, 1997447386, 6215980425, 18056320047, 49345966862, 127715626611, 314800577783, 742509146839, 1682790560239, 3677643193138, 7774488966837, 15941255148133
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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) = (883/1600593426432000)*n^18 + (883/16167610368000)*n^17 + (148963/62768369664000)*n^16 + (6599/108972864000)*n^15 + (8020459/7846046208000)*n^14 + (3062099/249080832000)*n^13 + (813101243/7242504192000)*n^12 + (165163519/201180672000)*n^11 + (1074230093/219469824000)*n^10 + (564482173/24385536000)*n^9 + (410608176823/4828336128000)*n^8 + (212043001/870912000)*n^7 + (12296690400809/23538138624000)*n^6 + (525004330021/653837184000)*n^5 + (1880413300609/1307674368000)*n^4 + (10237127057/6054048000)*n^3 + (183696263083/30875644800)*n^2 + (15176011/12252240)*n - 2
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EXAMPLE
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Some solutions for n=4
..0..1..1..2..3..4....0..1..2..2..3..4....0..1..1..2..3..3....0..1..1..2..3..3
..0..1..2..3..4..4....1..2..3..3..3..4....0..1..2..2..3..4....1..1..2..2..3..3
..1..2..3..4..4..4....2..3..3..3..3..4....0..1..2..3..4..5....1..2..2..3..3..4
..2..3..3..4..4..5....3..3..3..4..4..5....1..2..3..4..4..5....2..2..2..3..4..5
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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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