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%I #8 Jul 23 2017 03:08:11
%S 105,3465,74025,1346345,23079595,391180075,6719395683,118538975555,
%T 2163255564470,40995539853814,808279043604630,16591622809290774,
%U 354584560193653306,7886213669622441146,182405117548079061482,4383906242299647034026,109380730176142312738279
%N Number of permutations of [n] having exactly four nontrivial cycles.
%C A nontrivial cycle has size > 1.
%H Alois P. Heinz, <a href="/A289952/b289952.txt">Table of n, a(n) for n = 8..450</a>
%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Permutation">Permutation</a>
%F E.g.f.: (log(1-x)+x)^4/4!*exp(x).
%t Drop[Range[0, 30]! CoefficientList[Series[(Log[1 - x] + x)^4 / 4! Exp[x], {x, 0, 30}], x], 8] (* _Vincenzo Librandi_, Jul 23 2017 *)
%Y Column k=4 of A136394.
%K nonn
%O 8,1
%A _Alois P. Heinz_, Jul 16 2017
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