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A071181 Number of k such that phi(k) divides phi(n). 0


%S 2,2,5,5,9,5,9,9,9,9,7,9,19,9,14,14,20,9,13,14,19,7,7,14,16,19,13,19,

%T 11,14,13,20,16,20,34,19,31,13,34,20,30,19,13,16,34,7,7,20,13,16,27,

%U 34,11,13,30,34,31,11,7,20,37,13,31,27,51,16,13,27,14,34,9,34,63,31,30,31

%N Number of k such that phi(k) divides phi(n).

%o (PARI) for(n=1,100,print1(sum(i=1,1000,if(eulerphi(n)%eulerphi(i),0,1)),","))

%K easy,nonn

%O 1,1

%A _Benoit Cloitre_, Jun 10 2002

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Last modified February 12 15:22 EST 2016. Contains 268226 sequences.