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%I #13 Oct 12 2021 08:00:08
%S 6,10,14,15,18,20,22,26,30,34,35,38,39,40,45,46,48,50,51,52,54,55,58,
%T 60,62,68,70,74,75,78,82,85,86,87,90,94,95,96,98,100,102,104,105,106,
%U 110,111,112,115,116,118,119,120,122,123,134,135,136,140,142,143,144,146,148,150,153,155,156,158,159,160,162,164,165,166
%N Numbers k that are not prime powers, and have exactly phi(phi(k)) residues modulo k of the maximum order.
%C Numbers k with at least two distinct prime factors (A024619) such that A111725(k) = A010554(k).
%H Amiram Eldar, <a href="/A300080/b300080.txt">Table of n, a(n) for n = 1..10000</a>
%t q[n_] := Count[(t = Table[MultiplicativeOrder[k, n], {k, Select[Range[n], CoprimeQ[n, #] &]}]), Max[t]] == EulerPhi[EulerPhi[n]]; Select[Range[200], PrimeNu[#] > 1 && q[#] &] (* _Amiram Eldar_, Oct 12 2021 *)
%Y Set difference of: A300064 and A000961, A300079 and A246547, A024619 and A300065.
%Y Cf. A000010, A002322, A010554, A111725.
%K nonn
%O 1,1
%A _Max Alekseyev_, Feb 24 2018
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