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%I #14 Mar 31 2014 06:54:47
%S 7,23,29,47,79,83,89,101,107,113,131,137,149,157,163,173,181,193,197,
%T 227,229,241,257,271,293,311,331,347,353,379,383,397,401,421,439,449,
%U 457,461,499,521,557,563,599,601,607,617,619,641,643,647,659,673,701,719,769,821
%N Primes with primitive root 66.
%H Vincenzo Librandi, <a href="/A019389/b019389.txt">Table of n, a(n) for n = 1..1000</a>
%H <a href="/index/Pri#primes_root">Index entries for primes by primitive root</a>
%t pr=66; Select[Prime[Range[200]], MultiplicativeOrder[pr, # ] == #-1 &]
%K nonn
%O 1,1
%A _David W. Wilson_