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A223784
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Number of n X 3 0..2 arrays with rows, diagonals and antidiagonals unimodal.
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1
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22, 484, 8635, 151580, 2703137, 48302789, 862007289, 15379566078, 274427327200, 4896915028511, 87380287912506, 1559204462831053, 27822300189794631, 496458709513621497, 8858765510668046944, 158075026701646689756
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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) = 18*a(n-1) -24*a(n-2) +364*a(n-3) +605*a(n-4) -5879*a(n-5) -3267*a(n-6) -28514*a(n-7) -68422*a(n-8) +215872*a(n-9) +381625*a(n-10) +110428*a(n-11) +62650*a(n-12) -42873*a(n-13) -108576*a(n-14) -28080*a(n-15).
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EXAMPLE
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Some solutions for n=3
..0..1..1....0..2..2....0..2..1....0..1..2....0..2..0....0..0..1....0..2..2
..1..1..0....1..0..0....2..2..1....0..1..1....0..2..0....2..1..0....2..2..1
..1..1..0....0..2..1....2..2..1....1..1..1....0..0..1....2..2..0....0..0..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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