

A323576


Primes p such that 2 is a primitive root modulo p while 128 is not.


2



29, 197, 211, 379, 421, 491, 547, 659, 701, 757, 827, 883, 1373, 1499, 1667, 1877, 2213, 2269, 2339, 2437, 2549, 2843, 3011, 3067, 3347, 3557, 3571, 3613, 3851, 3907, 4019, 4229, 4243, 4397, 4621, 4691, 4789, 4957, 5573, 5741, 5923, 6203, 6469, 6637, 6763, 6917
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OFFSET

1,1


COMMENTS

Primes p such that 2 is a primitive root modulo p (i.e., p is in A001122) and that p == 1 (mod 7).
According to Artin's conjecture, the number of terms <= N is roughly ((6/41)*C)*PrimePi(N), where C is the Artin's constant = A005596, PrimePi = A000720. Compare: the number of terms of A001122 that are no greater than N is roughly C*PrimePi(N).


LINKS

Table of n, a(n) for n=1..46.
Eric Weisstein's World of Mathematics, Artin's constant
Wikipedia, Artin's conjecture on primitive roots


PROG

(PARI) forprime(p=3, 7000, if(znorder(Mod(2, p))==(p1) && p%7==1, print1(p, ", ")))


CROSSREFS

Cf. A001122, A005596, A000720.
Primes p such that 2 is a primitive root modulo p and that p == 1 (mod q): A307627 (q=3), A307628 (q=5), this sequence (q=7), A323577 (q=11), A323590 (q=13).
Sequence in context: A126497 A087767 A142226 * A142653 A237446 A144731
Adjacent sequences: A323573 A323574 A323575 * A323577 A323578 A323579


KEYWORD

nonn


AUTHOR

Jianing Song, Aug 30 2019


STATUS

approved



