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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 (list; graph; refs; listen; history; text; internal format)
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

Jianing Song, Table of n, a(n) for n = 1..1265

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

Cf. A061325, A061330.

Sequence in context: A204526 A206342 A031828 * A061325 A043677 A168462

Adjacent sequences:  A205578 A205579 A205580 * A205582 A205583 A205584

KEYWORD

nonn

AUTHOR

Emmanuel Vantieghem, Jan 29 2012

STATUS

approved

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Last modified January 19 00:03 EST 2021. Contains 340262 sequences. (Running on oeis4.)