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A060474 a(n) = denominator of phi(n)/(n+1), where phi(n) is Euler's phi, A000010.

%I A060474 #17 Oct 27 2023 22:05:37
%S A060474 2,3,2,5,3,7,4,9,5,11,6,13,7,5,2,17,9,19,10,21,11,23,12,25,13,9,14,29,
%T A060474 15,31,16,33,17,35,3,37,19,13,5,41,21,43,22,9,23,47,24,49,25,51,13,53,
%U A060474 27,55,7,19,29,59,30,61,31,21,16,65,11,67,34,69,35,71,36,73,37,25,19,77,13,79,40
%N A060474 a(n) = denominator of phi(n)/(n+1), where phi(n) is Euler's phi, A000010.
%H A060474 T. D. Noe, <a href="/A060474/b060474.txt">Table of n, a(n) for n = 1..1000</a>
%p A060474 with(numtheory,phi): seq(denom(phi(n)/(n+1)), n=1..50);
%t A060474 Denominator[Table[EulerPhi[n]/(n+1),{n,80}]] (* _Harvey P. Dale_, Apr 13 2012 *)
%o A060474 (PARI) { for (n=1, 1000, write("b060474.txt", n, " ", denominator(eulerphi(n)/(n + 1))); ) } \\ _Harry J. Smith_, Jul 13 2009
%o A060474 (Python)
%o A060474 from sympy import totient, gcd
%o A060474 def A060474(n): return (n+1)//gcd(n+1,totient(n)) # _Chai Wah Wu_, Apr 02 2021
%Y A060474 Cf. A000010, A060473.
%K A060474 easy,frac,nice,nonn
%O A060474 1,1
%A A060474 _Fabian Rothelius_, Mar 16 2001
%E A060474 More terms from _Asher Auel_, Mar 16 2001
%E A060474 A Maple program that should have been a PARI program removed by _Harry J. Smith_, Jul 13 2009