

A289951


Number of permutations of [n] having exactly three nontrivial cycles.


2



15, 315, 4480, 56672, 703430, 8941790, 118685336, 1658897240, 24494859389, 382301179169, 6302039460704, 109568927676192, 2005758201911884, 38588518087076860, 778794884783432176, 16458419973887378416, 363578176719852275467, 8381709371219530604071
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OFFSET

6,1


COMMENTS

A nontrivial cycle has size > 1.


LINKS

Alois P. Heinz, Table of n, a(n) for n = 6..450
Wikipedia, Permutation


FORMULA

E.g.f.: (log(1x)x)^3/3!*exp(x).


MATHEMATICA

Drop [Range[0, 30]! CoefficientList[Series[(Log[1  x]  x)^3 / 3! Exp[x], {x, 0, 30}], x], 6] (* Vincenzo Librandi, Jul 22 2017 *)


CROSSREFS

Column k=3 of A136394.
Sequence in context: A284070 A133766 A347980 * A112489 A062757 A088913
Adjacent sequences: A289948 A289949 A289950 * A289952 A289953 A289954


KEYWORD

nonn


AUTHOR

Alois P. Heinz, Jul 16 2017


STATUS

approved



