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 A175786 #15 Mar 14 2020 20:02:19 %S A175786 8,12,20,30,32,44,48,50,54,64,66,68,72,75,80,81,92,96,102,108,110,112, %T A175786 116,120,125,128,138,160,162,164,165,168,170,174,180,188,192,208,212, %U A175786 230,236,240,242,243,246,252,255,270,272,275,280,282,284,288,290,304 %N A175786 Numbers n such that the number of prime divisors of n (counted with multiplicity) is not a divisor of phi(n). %C A175786 a(n) is in the sequence if A001222(n) does not divides A000010(n). %H A175786 Enrique Pérez Herrero, <a href="/A175786/b175786.txt">Table of n, a(n) for n = 1..10000</a> %t A175786 Select[Range[2,400],Mod[EulerPhi[#],PrimeOmega[#]]!=0&] (* _Harvey P. Dale_, Mar 14 2020 *) %o A175786 (PARI) isok(n) = (eulerphi(n) % bigomega(n)); \\ _Michel Marcus_, Aug 27 2013 %Y A175786 Cf. A074946, A109421, A109423, A013929. %K A175786 nonn %O A175786 1,1 %A A175786 _Enrique Pérez Herrero_, Sep 04 2010