%I
%S 3,7,9,11,19,23,27,47,49,59,67,71,79,81,83,103,107,121,131,139,163,
%T 167,179,191,199,211,227,239,243,263,271,311,343,347,359,361,367,379,
%U 383,419,443,463,467,479,487,491,503,523,529,547,563,587,599,607,619,647
%N Numbers with primitive root 4.
%H Vincenzo Librandi, <a href="/A167800/b167800.txt">Table of n, a(n) for n = 1..1000</a>
%t pr=4; Select[Range[2,2000], MultiplicativeOrder[pr,# ] == EulerPhi[ # ] &]
%Y Cf. A105876 (primes with primitive root 4)
%K nonn
%O 1,1
%A _T. D. Noe_, Nov 12 2009
