A192218 Numbers n such that the number of distinct prime divisors of n divides phi(n).

2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 61, 62, 63, 64, 65, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77

Offset: 1

Author

Enrique Pérez Herrero, Aug 06 2011

Keywords

• nonn

Comments

Integers n where A001221(n) divides A000010(n).

Links

• G. C. Greubel, Table of n, a(n) for n = 1..5000

Crossrefs

Cf. A000010, A001221, A175785.

Programs

Mathematica

Select[Range[2,100],Divisible[EulerPhi[#],PrimeNu[#]]&] (* Harvey P. Dale, May 06 2013 *)

PARI

for(n=2,1e3,if(eulerphi(n)%omega(n)==0,print1(n", "))) \\ Charles R Greathouse IV, Aug 17 2011