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Integers k such that 28*phi(29*197^3*k) is not a totient number where phi is the totient function.
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%I #11 Mar 11 2023 04:02:33

%S 1,2,3,4,6,7517,15034,18059,22551,28019,30068,30983,36118,45102,56038,

%T 61966,65267,67427,67499,71387,84057,84947,90677,92949,97187,112076,

%U 115469,123932,127487,130534,130787,134854,134998,142774,168114,169067,169894,181354,185898,191579,194374,195801

%N Integers k such that 28*phi(29*197^3*k) is not a totient number where phi is the totient function.

%C For k=1, A000010(29*197^3) = 212983792 = A361058(28).

%H Math Overflow, <a href="https://mathoverflow.net/questions/307392/the-range-of-the-euler-totient-function-and-multiplication-by-28">The range of the Euler totient function and multiplication by 28</a>, 2018.

%o (PARI) isok(k) = ! istotient(28*eulerphi(29*197^3*k));

%Y Cf. A000010, A007617, A361058.

%K nonn

%O 1,2

%A _Michel Marcus_, Mar 10 2023