

A109661


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


0



1, 9, 18, 23, 45, 172, 578, 4788, 6039, 6408, 10303
(list;
graph;
refs;
listen;
history;
text;
internal format)



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



