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A077080 a(n) = phi(sigma(n) + phi(n)) = A000010(A000203(n) + A000010(n)) = A000010(A065387(n)). 5

%I #7 Mar 16 2015 12:09:00

%S 1,2,2,6,4,6,6,18,18,10,10,16,12,8,16,24,16,24,18,20,20,22,22,32,32,

%T 18,28,32,28,32,30,78,32,24,24,102,36,24,32,52,40,36,42,48,32,46,46,

%U 48,60,112,48,60,52,44,48,48,56,58,58,88,60,36,48,104,40,80,66,78,48,48,70

%N a(n) = phi(sigma(n) + phi(n)) = A000010(A000203(n) + A000010(n)) = A000010(A065387(n)).

%t Table[EulerPhi[DivisorSigma[1,n]+EulerPhi[n]],{n,80}] (* _Harvey P. Dale_, Mar 16 2015 *)

%o (PARI) a(n)=eulerphi(sigma(n)+eulerphi(n)) \\ _Charles R Greathouse IV_, Feb 14 2013

%Y Cf. A000010, A000203, A065387, A077081-A077085.

%K nonn

%O 1,2

%A _Labos Elemer_, Oct 28 2002

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Last modified April 24 09:18 EDT 2024. Contains 371935 sequences. (Running on oeis4.)