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%I #3 Mar 30 2012 17:37:43
%S 1,2,3,4,652245
%N Numbers n such that prime(n)=d(n)*phi(n)+1, where d(n) is number of positive divisors of n.
%C There is no further term up to 5*10^7.
%e 652245 is in the sequence because prime(652245)=d(652245)*phi(652245)+1.
%t Do[If[Prime[n] == DivisorSigma[0, n]*EulerPhi[n] + 1, Print[n]], {n, 50000000}]
%Y Cf. A104905, A107657.
%K more,nonn
%O 1,2
%A _Farideh Firoozbakht_, Jun 06 2005
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