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%I #7 Oct 18 2014 09:30:41
%S 1,9,18,23,45,172,578,4788,6039,6408,10303
%N Numbers n such that the sum of the digits of phi(n)^n is divisible by n.
%C Next term after 6408 is greater than 10000.
%e The sum of the digits of phi(6039)^6039 is 42273 and 42273 is divisible by 6039, so 6039 is in the sequence.
%t Do[s = EulerPhi[n]^n; k = Plus @@ IntegerDigits[s]; If[Mod[k, n] == 0, Print[n]], {n, 1, 10000}]
%t Select[Range[11000],Divisible[Total[IntegerDigits[EulerPhi[#]^#]],#]&] (* _Harvey P. Dale_, Oct 18 2014 *)
%K base,nonn
%O 1,2
%A _Ryan Propper_, Aug 06 2005
%E a(11) from _Stefan Steinerberger_, Jan 24 2006
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