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A205581 Primes p whose smallest positive primitive root (mod p) is not squarefree. 1

%I

%S 4111,7841,10111,15391,15991,16061,20011,21031,22699,32299,32957,

%T 35911,43963,45127,45631,47431,49831,51199,53173,53731,58111,59671,

%U 60331,64231,71761,74311,76039,78079,81331,81761,83311,83431,87541,98911,100621,102871,104729

%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[10000]],!SquareFreeQ[PrimitiveRoot[#]]&] (* version 7.0 *)

%o (PARI) lista(nn) = forprime(p=2, nn, if (! issquarefree(lift(znprimroot(p))), print1(p, ", ")));

%Y Cf. A061325, A061330.

%K nonn

%O 1,1

%A _Emmanuel Vantieghem_, Jan 29 2012

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Last modified March 8 11:34 EST 2021. Contains 341948 sequences. (Running on oeis4.)