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%I #4 Feb 05 2013 18:01:18
%S 2,3,4,5,6,7,10,11,13,16,17,19,22,23,25,27,29,31,37,40,41,43,46,47,52,
%T 53,58,59,61,64,67,68,71,72,73,79,80,82,83,89,97,98,101,103,106,107,
%U 109,113,117,127,128,131,136,137,139,144,149,151,157,162,163,166,167
%N phi(n) + sigma(n) gives a semiprime (A001358).
%e phi(101)+sigma(101)=202=2*101.
%t Select[Range[200],PrimeOmega[EulerPhi[#]+DivisorSigma[1,#]]==2&] (* _Harvey P. Dale_, Feb 05 2013 *)
%Y Cf. A001358, A116016, A116001.
%K nonn
%O 1,1
%A _Giovanni Resta_, Feb 13 2006
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