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A192218 Numbers n such that the number of distinct prime divisors of n divides phi(n). 2
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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

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

LINKS

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

MATHEMATICA

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

PROG

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

CROSSREFS

Cf. A000010, A001221, A175785.

Sequence in context: A246103 A281873 A273888 * A070915 A004441 A004438

Adjacent sequences:  A192215 A192216 A192217 * A192219 A192220 A192221

KEYWORD

nonn

AUTHOR

Enrique Pérez Herrero, Aug 06 2011

STATUS

approved

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Last modified March 26 20:47 EDT 2019. Contains 321535 sequences. (Running on oeis4.)