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

KEYWORD

nonn

AUTHOR

Emmanuel Vantieghem, Jan 29 2012

STATUS

approved