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A289955
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Number of permutations of [n] having exactly seven nontrivial cycles.
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2
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135135, 11486475, 583783200, 23434451040, 828052325100, 27221423409180, 859752405431920, 26617555964919920, 818486200464162230, 25221598500336187950, 783666055857936771520, 24658659357394687609600, 788174700361283653718300, 25647112073453527447490700
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OFFSET
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14,1
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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)^7/7!*exp(x).
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MATHEMATICA
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Drop[CoefficientList[Series[(-Log[1 - x] - x)^7/7!*Exp[x] , {x, 0, 50}], x] * Table[k !, {k, 0, 50}] , 14] (* Indranil Ghosh, Jul 16 2017 *)
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PROG
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(PARI) x = 'x + O('x^30); Vec(serlaplace((-log(1-x)-x)^7/7!*exp(x))) \\ Michel Marcus, Jul 16 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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