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%I #5 Mar 31 2014 01:49:31
%S 2,4,5,7,10,14,17,19,25,29,31,34,38,43,49,50,53,58,62,79,86,89,98,101,
%T 106,113,125,127,137,139,149,158,163,173,178,197,199,202,211,223,226,
%U 233,250,254,257,269,274,278,281,283,289,293,298,317,326,331,343,346
%N Numbers with primitive root 3.
%H Vincenzo Librandi, <a href="/A167792/b167792.txt">Table of n, a(n) for n = 1..1000</a>
%t pr=3; Select[Range[2,2000], MultiplicativeOrder[pr,# ] == EulerPhi[ # ] &]
%Y Cf. A019334 (primes with primitive root 3)
%K nonn
%O 1,1
%A _T. D. Noe_, Nov 12 2009