%N Primes p whose smallest positive primitive root (mod p) is not squarefree.
%C A061325 is a proper subsequence.
%C A061330 is also a proper subsequence. - _Michel Marcus_, Feb 09 2016
%C Most of the terms have least primitive root 12. - _Jianing Song_, Aug 29 2018
%H Jianing Song, <a href="/A205581/b205581.txt">Table of n, a(n) for n = 1..1265</a>
%H Stephen D. Cohen, Tim Trudgian, <a href="http://arxiv.org/abs/1602.02440">On the least square-free primitive root modulo p</a>, arXiv:1602.02440 [math.NT], 2016.
%e 4111 is in the sequence since it is prime and its smallest primitive root (mod 4111) is 12.
%e 53173 is in the sequence since it is prime and its smallest primitive root (mod 53173) is 18.
%t Select[Prime[Range],!SquareFreeQ[PrimitiveRoot[#]]&] (* version 7.0 *)
%o (PARI) lista(nn) = forprime(p=2, nn, if (! issquarefree(lift(znprimroot(p))), print1(p, ", ")));
%Y Cf. A061325, A061330.
%A _Emmanuel Vantieghem_, Jan 29 2012