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A205581
Primes p whose smallest positive primitive root (mod p) is not squarefree.
1
4111, 7841, 10111, 15391, 15991, 16061, 20011, 21031, 22699, 32299, 32957, 35911, 43963, 45127, 45631, 47431, 49831, 51199, 53173, 53731, 58111, 59671, 60331, 64231, 71761, 74311, 76039, 78079, 81331, 81761, 83311, 83431, 87541, 98911, 100621, 102871, 104729
OFFSET
1,1
COMMENTS
A061325 is a proper subsequence.
A061330 is also a proper subsequence. - Michel Marcus, Feb 09 2016
Most of the terms have least primitive root 12. - Jianing Song, Aug 29 2018
LINKS
Stephen D. Cohen, Tim Trudgian, On the least square-free primitive root modulo p, arXiv:1602.02440 [math.NT], 2016.
EXAMPLE
4111 is in the sequence since it is prime and its smallest primitive root (mod 4111) is 12.
53173 is in the sequence since it is prime and its smallest primitive root (mod 53173) is 18.
MATHEMATICA
Select[Prime[Range[10000]], !SquareFreeQ[PrimitiveRoot[#]]&] (* version 7.0 *)
PROG
(PARI) lista(nn) = forprime(p=2, nn, if (! issquarefree(lift(znprimroot(p))), print1(p, ", ")));
CROSSREFS
Sequence in context: A204526 A206342 A031828 * A061325 A043677 A168462
KEYWORD
nonn
AUTHOR
Emmanuel Vantieghem, Jan 29 2012
STATUS
approved