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A063667 Number of solutions of EulerPhi[x]=12n+2. 1


%S 0,0,0,0,0,0,0,0,2,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,

%T 0,0,0,0,0,0,0,2,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,

%U 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0

%N Number of solutions of EulerPhi[x]=12n+2.

%e Among the first 10000 cases only 16 invphi(12j+2) set are non-empty, always with 2 terms. E.g. n=8034, a(8034)=2 because 12*8034+2=96410 and invphi(96410)={96721,193442}.

%p with(numtheory): [seq(nops(invphi(2+12*j)),j=1..10000)];

%Y A000010, A005277, A002202.

%K nonn

%O 1,9

%A _Labos Elemer_, Aug 22 2001

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Last modified November 27 17:47 EST 2015. Contains 264550 sequences.