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%I #10 Apr 29 2022 12:01:20
%S 1,5,6,11,10,10,15,14,15,23,20,25,21,22,33,26,26,31,35,30,47,33,34,35,
%T 50,38,39,55,42,55,50,46,69,50,52,51,65,62,55,77,57,58,75,62,70,95,65,
%U 66,85,69,70,110,74,78,95,77,78,115,94,82,105,85,86,87,121,100,91,115
%N Values of phi(k)*Sum_{d|k} 1/phi(d) for nonprimes k.
%H Amiram Eldar, <a href="/A069170/b069170.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = A069208(A018252(n)). - _Amiram Eldar_, Apr 29 2022
%t f[p_, e_] := (p^(e + 1) - p^e + p^(e - 1) - 1)/(p - 1); s[1] = 1; s[n_] := Times @@ f @@@ FactorInteger[n]; s /@ Select[Range[100], !PrimeQ[#] &] (* _Amiram Eldar_, Apr 29 2022 *)
%Y Cf. A000010, A018252, A069208.
%K easy,nonn
%O 1,2
%A _Benoit Cloitre_, Apr 09 2002
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