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A223916
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Number of nX6 0..2 arrays with rows and antidiagonals unimodal and columns nondecreasing
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1
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148, 4102, 45988, 323394, 1721356, 7526024, 28247478, 93683295, 280338123, 769012348, 1958026231, 4673735444, 10543684618, 22631328296, 46477583300, 91756934105, 174838318505, 322648096420, 578369211133, 1009683032422
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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) = (761/8553600)*n^12 + (761/475200)*n^11 + (21583/1088640)*n^10 + (458/2835)*n^9 + (1760837/1814400)*n^8 + (1346021/302400)*n^7 + (430403/31104)*n^6 + (19199/480)*n^5 + (88406683/1360800)*n^4 + (13099679/226800)*n^3 - (3421811/41580)*n^2 - (5265011/13860)*n + 389 for n>3
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EXAMPLE
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Some solutions for n=3
..1..1..1..0..0..0....1..1..1..1..1..0....0..0..1..1..0..0....0..1..0..0..0..0
..1..1..1..1..0..0....1..1..1..1..2..1....0..1..2..2..2..1....1..1..1..0..0..0
..1..1..2..2..2..1....1..2..2..2..2..1....1..1..2..2..2..1....1..1..1..2..2..2
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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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