%I #9 Mar 31 2024 15:13:09
%S 7,41,61,83,89,107,109,127,139,173,193,197,211,227,239,281,293,311,
%T 317,331,347,349,359,367,421,431,433,443,449,457,463,467,479,487,499,
%U 521,541,557,563,569,571,577,587,599,607,619,641,653,673,677,683,719,727,739,761
%N Primes for which -30 is a primitive root.
%H Vincenzo Librandi, <a href="/A105902/b105902.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=-30; Select[Prime[Range[200]], MultiplicativeOrder[pr, # ] == #-1 &]
%K nonn
%O 1,1
%A _N. J. A. Sloane_, Apr 24 2005