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A223966
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Number of 6Xn 0..3 arrays with antidiagonals unimodal and rows and diagonals nondecreasing
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1
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4096, 403104, 5777663, 37844037, 163752797, 556027700, 1629022329, 4351046624, 10953882109, 26519610433, 62472567689, 144124515790, 326646013571, 728132468716, 1596498777021, 3441674914130, 7290815852670, 15169818503342
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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) = (1/73156608000)*n^18 + (1/2709504000)*n^17 + (3319/268240896000)*n^16 + (247579/871782912000)*n^15 + (1111849/193729536000)*n^14 + (3684553/35582976000)*n^13 + (658841977/402361344000)*n^12 + (521443357/22353408000)*n^11 + (7665391471/24385536000)*n^10 + (90826901857/24385536000)*n^9 + (333381059779/8128512000)*n^8 + (85061672873/217728000)*n^7 + (319642737999043/100590336000)*n^6 + (118989237432757/5588352000)*n^5 + (107614272658699/1862784000)*n^4 + (891088311042211/9081072000)*n^3 - (51719689062621/11211200)*n^2 + (1774047167507/360360)*n + 34898064 for n>11
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EXAMPLE
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Some solutions for n=3
..0..0..0....0..0..2....0..0..0....0..0..0....0..0..0....0..0..0....0..0..0
..0..0..0....0..0..1....0..0..1....0..0..0....0..0..1....0..0..0....0..0..0
..0..1..1....0..1..1....2..2..3....0..0..2....0..2..2....0..0..0....0..0..2
..0..1..3....1..1..2....0..2..2....0..1..2....0..3..3....0..2..2....1..1..3
..0..0..2....0..1..2....0..1..2....0..0..3....2..2..3....1..2..3....1..3..3
..0..1..3....0..2..2....0..2..2....0..1..1....0..2..2....1..2..2....1..2..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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