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%I #15 Oct 11 2021 04:37:18
%S 223,379,463,631,691,883,907,1051,1423,1447,1543,1723,1747,1783,1987,
%T 2143,2179,2347,2467,2591,2767,3259,3307,3511,3631,3691,3739,3823,
%U 3907,4219,4447,4507,4519,4639,4987,5023,5107,5119,5347,5683,5923
%N Primes p for which there are more primitive roots below p/2 than above p/2.
%C All terms are of the form 4*m + 3 (see A172480 and A172490). - _Emmanuel Vantieghem_, Nov 07 2016
%H Amiram Eldar, <a href="/A118818/b118818.txt">Table of n, a(n) for n = 1..1000</a>
%e 223 is a term because it has 38 primitive roots below 111.5, but 34 above 111.5.
%t q[n_] := PrimeQ[n] && Length[(p = PrimitiveRootList[n])] > 2*Count[p, _?(# > n/2 &)]; Select[4*Range[0, 1500] + 3, q] (* _Amiram Eldar_, Oct 11 2021 *)
%Y Cf. A128859, A172480, A172490.
%K nonn
%O 1,1
%A _Don Reble_, Apr 20 2007