This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A361396 #11 Mar 11 2023 04:02:33 %S A361396 1,2,3,4,6,7517,15034,18059,22551,28019,30068,30983,36118,45102,56038, %T A361396 61966,65267,67427,67499,71387,84057,84947,90677,92949,97187,112076, %U A361396 115469,123932,127487,130534,130787,134854,134998,142774,168114,169067,169894,181354,185898,191579,194374,195801 %N A361396 Integers k such that 28*phi(29*197^3*k) is not a totient number where phi is the totient function. %C A361396 For k=1, A000010(29*197^3) = 212983792 = A361058(28). %H A361396 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 A361396 (PARI) isok(k) = ! istotient(28*eulerphi(29*197^3*k)); %Y A361396 Cf. A000010, A007617, A361058. %K A361396 nonn %O A361396 1,2 %A A361396 _Michel Marcus_, Mar 10 2023