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A223721
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Number of nX4 0..2 arrays with rows, antidiagonals and columns unimodal
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1
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46, 2116, 46613, 608855, 5537147, 38566854, 218619076, 1051051942, 4413826871, 16548850432, 56334327215, 176427795883, 513754867486, 1403147317562, 3620163947216, 8876634938318, 20791393840502, 46723393566999
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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) = (456419/5230697472000)*n^16 + (299363/186810624000)*n^15 + (8437981/261534873600)*n^14 + (678959/1868106240)*n^13 + (91942579/28740096000)*n^12 + (161673031/7185024000)*n^11 + (203867119/1828915200)*n^10 + (37055/81648)*n^9 + (59612358509/36578304000)*n^8 + (2850286193/1306368000)*n^7 + (7237625987/718502400)*n^6 + (573765127/143700480)*n^5 - (109277252779/4036032000)*n^4 + (59181202013/216216000)*n^3 - (12927784033/16816800)*n^2 + (36815651/36036)*n - 470 for n>2
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EXAMPLE
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Some solutions for n=3
..0..0..1..2....1..2..2..1....1..1..0..0....1..2..0..0....0..0..1..2
..0..1..2..2....0..2..2..2....1..1..1..0....1..2..2..1....0..1..2..2
..0..1..2..2....0..0..2..0....0..1..2..0....2..1..1..0....2..1..1..0
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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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