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A217885
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Number of n element 1..n arrays with each element the minimum of 2 adjacent elements of a permutation of 1..n+1 of n+1 elements
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0
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1, 3, 10, 40, 182, 938, 5424, 34788, 244544, 1865144, 15312976, 134495328, 1257334432, 12456693168, 130288665568, 1433829681568
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OFFSET
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1,2
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COMMENTS
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LINKS
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EXAMPLE
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Some solutions for n=4
..2....3....3....1....4....1....1....1....1....1....2....2....1....2....4....3
..1....4....2....2....1....3....2....1....1....3....3....1....1....4....3....3
..1....2....2....2....1....4....3....4....3....2....3....1....3....1....1....2
..4....1....1....4....2....2....4....2....4....2....1....3....3....1....1....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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