A137150 Degree of Lagrange resolvent of polynomial of composite degree.

1, 3, 60, 1260, 6720, 90720, 9979200, 1037836800, 10897286400, 163459296000, 59281238016000, 15205637551104000, 202741834014720000, 5109094217170944000, 3231502092360622080000, 31022420086661971968000

Offset

1,2

Comments

Ratio: degree of symmetric group of composite order n divided by order metacyclic group of composite order n.

Links

Vincenzo Librandi, Table of n, a(n) for n = 1..300

Formula

a(n) = n!/(n EulerPhi[n]) for composite n A058161 = A137149 + A137150.

Mathematica

a = {}; Do[If[PrimeQ[n], [null], AppendTo[a, n!/(n EulerPhi[n])]], {n, 1, 30}]; a
With[{nn=30}, #!/(# EulerPhi[#])&/@Complement[Range[nn], Prime[Range[ PrimePi[ nn]]]]] (* Harvey P. Dale, Jul 05 2014 *)

Crossrefs

Cf. A058161, A137149.

Sequence in context: A065889 A183251 A001084 * A248707 A219870 A326283

Adjacent sequences: A137147 A137148 A137149 * A137151 A137152 A137153

Keyword

nonn

Author

Artur Jasinski, Jan 23 2008

Status

approved