A133119 Number of permutations of [n] with 3 cycle lengths.
120, 1050, 12712, 141876, 1418400, 17061660, 212254548, 2735287698, 37354035628, 581350330470, 8895742806480, 151305163230480, 2659183039338192, 50112909523522476, 976443721325014300, 20413628375979803370, 434137453618439716068
Offset: 6
Links
- Alois P. Heinz, Table of n, a(n) for n = 6..200
Formula
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.
Extensions
More terms from Max Alekseyev, Feb 08 2010