A109661 Numbers n such that the sum of the digits of phi(n)^n is divisible by n.

1, 9, 18, 23, 45, 172, 578, 4788, 6039, 6408, 10303

Offset

1,2

Comments

Next term after 6408 is greater than 10000.

Links

Table of n, a(n) for n=1..11.

Example

The sum of the digits of phi(6039)^6039 is 42273 and 42273 is divisible by 6039, so 6039 is in the sequence.

Mathematica

Do[s = EulerPhi[n]^n; k = Plus @@ IntegerDigits[s]; If[Mod[k, n] == 0, Print[n]], {n, 1, 10000}]
Select[Range[11000], Divisible[Total[IntegerDigits[EulerPhi[#]^#]], #]&] (* Harvey P. Dale, Oct 18 2014 *)

Crossrefs

Sequence in context: A046412 A171081 A232056 * A015798 A028494 A167663

Adjacent sequences: A109658 A109659 A109660 * A109662 A109663 A109664

Keyword

base,nonn

Author

Ryan Propper, Aug 06 2005

Extensions

a(11) from Stefan Steinerberger, Jan 24 2006

Status

approved