A289954 Number of permutations of [n] having exactly six nontrivial cycles.

10395, 675675, 26801775, 855870015, 24479795340, 661680519500, 17424049022380, 455359195951660, 11950227130952110, 317363732767667950, 8572733672197564870, 236346930206430701350, 6665648338618807806268, 192596934884274256728700, 5706700987506640526104700

Offset

12,1

Comments

A nontrivial cycle has size > 1.

Links

Alois P. Heinz, Table of n, a(n) for n = 12..450

Wikipedia, Permutation

Formula

E.g.f.: (log(1-x)+x)^6/6!*exp(x).

Mathematica

Drop[Range[0, 30]! CoefficientList[Series[(Log[1 - x] + x)^6 / 6! Exp[x], {x, 0, 30}], x], 12] (* Vincenzo Librandi, Jul 24 2017 *)

Prog

(PARI) x = 'x + O('x^30); Vec(serlaplace((log(1-x)+x)^6/6!*exp(x))) \\ Michel Marcus, Jul 24 2017

Crossrefs

Column k=6 of A136394.

Sequence in context: A271766 A104439 A290035 * A263890 A279946 A031866

Adjacent sequences: A289951 A289952 A289953 * A289955 A289956 A289957

Keyword

nonn

Author

Alois P. Heinz, Jul 16 2017

Status

approved