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%I #10 Jul 22 2017 09:23:11
%S 15,315,4480,56672,703430,8941790,118685336,1658897240,24494859389,
%T 382301179169,6302039460704,109568927676192,2005758201911884,
%U 38588518087076860,778794884783432176,16458419973887378416,363578176719852275467,8381709371219530604071
%N Number of permutations of [n] having exactly three nontrivial cycles.
%C A nontrivial cycle has size > 1.
%H Alois P. Heinz, <a href="/A289951/b289951.txt">Table of n, a(n) for n = 6..450</a>
%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Permutation">Permutation</a>
%F E.g.f.: (-log(1-x)-x)^3/3!*exp(x).
%t Drop [Range[0, 30]! CoefficientList[Series[(-Log[1 - x] - x)^3 / 3! Exp[x], {x, 0, 30}], x], 6] (* _Vincenzo Librandi_, Jul 22 2017 *)
%Y Column k=3 of A136394.
%K nonn
%O 6,1
%A _Alois P. Heinz_, Jul 16 2017
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