%I #10 Aug 03 2017 01:29:02
%S 5,17,51,73,109,433,17408,21601,121501,1350001,3294173,9376762501
%N phi(n) is equal to the product of the dual primepower components of n1 (i.e., A008477(n1)).
%C a(13) > 3*10^10.  _Donovan Johnson_
%e phi(17408) = 8192, 17407 = 13^2*103^1, (2^13)*(1^103) = 8192.
%Y Cf. A000010, A008477.
%K nonn
%O 1,1
%A _Olivier GĂ©rard_
%E More terms from _Naohiro Nomoto_, Jun 24 2001
%E a(12) from _Donovan Johnson_, Nov 14 2010
