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Number of permutations of [n] with 3 cycle lengths.
2

%I #10 Aug 21 2014 18:00:59

%S 120,1050,12712,141876,1418400,17061660,212254548,2735287698,

%T 37354035628,581350330470,8895742806480,151305163230480,

%U 2659183039338192,50112909523522476,976443721325014300,20413628375979803370,434137453618439716068

%N Number of permutations of [n] with 3 cycle lengths.

%H Alois P. Heinz, <a href="/A133119/b133119.txt">Table of n, a(n) for n = 6..200</a>

%F We obtain e.g.f. for number of permutations of [n] with m cycle lengths if we substitute x(i) with -Sum_{k>0} ((1-exp(x^k/k))^i in cycle index Z(S(m); x(1),x(2),..,x(m)) of symmetric group S(m) of degree m.

%Y Cf. A005225, A005772, A038041, A088142.

%Y Column k=3 of A218868.

%K easy,nonn

%O 6,1

%A _Vladeta Jovovic_, Sep 18 2007

%E More terms from _Max Alekseyev_, Feb 08 2010