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A369074
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Number of permutations of [n] such that for each cycle the arithmetic mean of the elements is an integer.
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1
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1, 1, 1, 4, 8, 50, 144, 1416, 4956, 73776, 257040, 5945376, 27326592, 741487104, 2932516224, 131001886656, 638526753792, 29531870206848
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OFFSET
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0,4
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LINKS
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EXAMPLE
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a(0) = 1: the empty permutation.
a(1) = 1: (1).
a(2) = 1: (1)(2).
a(3) = 4: (123), (132), (13)(2), (1)(2)(3).
a(4) = 8: (123)(4), (132)(4), (13)(24), (13)(2)(4), (1)(234), (1)(243),
(1)(24)(3), (1)(2)(3)(4).
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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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STATUS
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approved
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