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A289951
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Number of permutations of [n] having exactly three nontrivial cycles.
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2
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15, 315, 4480, 56672, 703430, 8941790, 118685336, 1658897240, 24494859389, 382301179169, 6302039460704, 109568927676192, 2005758201911884, 38588518087076860, 778794884783432176, 16458419973887378416, 363578176719852275467, 8381709371219530604071
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OFFSET
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6,1
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COMMENTS
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A nontrivial cycle has size > 1.
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LINKS
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FORMULA
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E.g.f.: (-log(1-x)-x)^3/3!*exp(x).
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MATHEMATICA
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Drop [Range[0, 30]! CoefficientList[Series[(-Log[1 - x] - x)^3 / 3! Exp[x], {x, 0, 30}], x], 6] (* Vincenzo Librandi, Jul 22 2017 *)
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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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