The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A067583 Integers of the form phi(n^n)/phi(n)^n where phi is the Euler totient function A000010(n). 0

%I

%S 1,2,8,243,128,177147,32768,129140163,94143178827,2147483648,

%T 50031545098999707,26588814358957503287787,19383245667680019896796723,

%U 9223372036854775808,7509466514979724803946715958257547

%N Integers of the form phi(n^n)/phi(n)^n where phi is the Euler totient function A000010(n).

%F If A007694(n)==0 (mod 3) (or equivalently if A007694(n) = 2^u*3^v with u, v >=1) then a(n) =3^(A007694(n) -1); if A007694(n)=2^u a(n)=2^(A007694(n) -1). Remark : if n=3^v phi(n^n)/phi(n)^n=1/2^(n-1)

%K nonn

%O 1,2

%A _Benoit Cloitre_, Jan 30 2002

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified April 10 15:07 EDT 2021. Contains 342845 sequences. (Running on oeis4.)