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A209325
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Number of permutations of [n] with a succession but no fixed points.
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2
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0, 0, 0, 2, 5, 30, 163, 1172, 9349, 84208, 842149, 9266416, 111220875, 1446134218, 20248984181, 303774206310, 4860923772369, 82643503648838, 1487703851220935, 28268359232622252, 565401755237435337, 11874072125853230504, 261241878854832755345
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OFFSET
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0,4
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COMMENTS
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A succession of a permutation p is a position i such that p(i+1)-p(i) = 1.
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LINKS
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FORMULA
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EXAMPLE
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For n=4 we have 2341, 3412, 3421, 4123 and 4312.
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CROSSREFS
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KEYWORD
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nonn,more
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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