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%I #20 Oct 12 2021 07:59:42
%S 8,12,21,24,28,33,36,42,44,56,57,63,65,66,69,72,76,77,80,84,88,91,92,
%T 93,99,108,114,117,124,126,129,130,132,133,138,141,145,147,152,154,
%U 161,168,171,172,177,182,184,185,186,188,189,195,196,198,201,207,208,209,213,216,217,228,231,234,236,237,240,248,249,252,253,258,260,264,265,266,268,273,275,276,279,282
%N Numbers k such that the number of residues modulo k of the maximum order is different from phi(phi(k)).
%C Numbers k such that A111725(k) is not equal to A010554(k).
%C The ratio a(n)/n tends to 1 as n grows.
%H Amiram Eldar, <a href="/A300065/b300065.txt">Table of n, a(n) for n = 1..10000</a>
%H Peter J. Cameron and D. A. Preece, <a href="https://cameroncounts.files.wordpress.com/2014/01/plr1.pdf">Primitive lambda-roots</a>, 2014.
%H T. W. Müller and J.-C. Schlage-Puchta, <a href="https://doi.org/10.4064/aa115-3-2">On the number of primitive lambda-roots</a>, Acta Arithmetica, Vol. 115 (2004), pp. 217-223.
%t q[n_] := Count[(t = Table[MultiplicativeOrder[k, n], {k, Select[Range[n], CoprimeQ[n, #] &]}]), Max[t]] != EulerPhi[EulerPhi[n]]; Select[Range[300], q] (* _Amiram Eldar_, Oct 12 2021 *)
%Y Complement of A300064.
%Y Union of {8} and set difference of A024619 and A300080.
%Y Cf. A000010, A002322, A010554, A111725, A300079.
%K nonn
%O 1,1
%A _Max Alekseyev_, Feb 23 2018