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%I
%S 1,2,3,6,9,15,18,27,30,39,54,78,81,111,162,183,222,243,255,327,363,
%T 366,471,486,510,654,726,729,942,1458,2187,2199,3063,4359,4374,4375,
%U 4398,5571,6126,6561,8718,8750,8751,11142,13122,15723,17502,19683
%N Positive integers n such that S(n) divides n, where S(n) is the sum of the iterates of the Euler phi-function of n, that is, S(n) = phi(n)+phi(phi(n))+....+ 1.
%D Igor E. Shparlinski, On the sum of iterations of the Euler function, Journal of Integer Sequences, Volume 9 (2006), Article 06.1.6.
%e 18 is in the sequence because phi(18)+phi(phi(18))+phi(phi(phi(18))) = 6 + 2 + 1 = 9, which divides 18.
%Y Cf. A082897.
%K nonn
%O 1,2
%A __Jeffrey Shallit__, Jan 22 2006
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