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 A241195 #22 Mar 24 2025 22:35:20
%S A241195 1,2,2,3,5,3,2,3,11,7,15,3,5,7,23,13,29,15,33,35,3,13,41,11,3,5,51,53,
%T A241195 3,7,7,65,17,69,37,15,13,3,83,43,89,15,95,3,7,33,35,37,113,19,29,119,
%U A241195 15,5,2,131,67,15,69,35,141,73,51,31,13,79,33,7,173,87,11
%N A241195 Denominator of phi(prime(n)-1)/(prime(n)-1), where phi is Euler's totient function and prime(n) is the n-th prime.
%C A241195 The numerators are in A241194.
%H A241195 T. D. Noe, <a href="/A241195/b241195.txt">Table of n, a(n) for n = 1..10000</a>
%F A241195 a(n) = A109395(A006093(n)). - _Ridouane Oudra_, Mar 24 2025
%p A241195 with(numtheory): A241195:=n->denom(phi(ithprime(n)-1) / (ithprime(n)-1)): seq(A241195(n), n=1..100); # _Wesley Ivan Hurt_, Apr 06 2015
%t A241195 Denominator[Table[EulerPhi[p - 1]/(p - 1), {p, Prime[Range[100]]}]]
%o A241195 (PARI) lista(nn) = forprime(p=2, nn, print1(denominator(eulerphi(p-1)/(p-1)), ", ")); \\ _Michel Marcus_, Jan 03 2015
%o A241195 (Magma) [Denominator(EulerPhi(NthPrime(n)-1)/(NthPrime(n)-1)): n in [1..80]]; // _Vincenzo Librandi_, Apr 06 2015
%Y A241195 Cf. A000010 (phi), A241194 (numerators).
%Y A241195 Cf. A109395, A006093.
%K A241195 nonn,frac
%O A241195 1,2
%A A241195 _T. D. Noe_, Apr 17 2014