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A223943
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Number of n X n 0..1 arrays with diagonals and antidiagonals unimodal and rows nondecreasing.
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0
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2, 9, 54, 321, 1821, 9919, 52532, 272997, 1401993, 7150718, 36352875, 184670276, 938969921, 4783571827, 24431153268, 125119394092
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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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EXAMPLE
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Some solutions for n=3
..0..1..1....0..0..0....0..0..0....0..1..1....0..0..0....0..0..0....0..1..1
..0..0..0....0..0..1....1..1..1....0..0..1....0..0..1....0..1..1....0..0..0
..0..0..0....0..0..1....0..0..1....0..0..1....0..0..0....0..0..1....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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