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A377178
Primes p such that 9/2 is a primitive root modulo p.
6
5, 13, 19, 29, 43, 53, 59, 61, 83, 101, 107, 109, 149, 157, 173, 179, 197, 227, 229, 251, 269, 277, 283, 293, 317, 331, 347, 373, 389, 419, 443, 461, 467, 491, 509, 523, 547, 557, 563, 587, 613, 619, 653, 661, 677, 683, 691, 701, 709, 733, 739, 757, 773, 787, 797, 821, 829, 853, 883, 907, 947, 971
OFFSET
1,1
COMMENTS
If p is a term in this sequence, then 9/2 is not a square modulo p (i.e., p is in A003629).
Conjecture: this sequence has relative density equal to Artin's constant (A005596) with respect to the set of primes.
PROG
(PARI) forprime(p=5, 10^3, if(znorder(Mod(9/2, p))==p-1, print1(p, ", ")));
CROSSREFS
Primes p such that +a/2 is a primitive root modulo p: A320384 (a=3), A377174 (a=5), A377176 (a=7), this sequence (a=9).
Primes p such that -a/2 is a primitive root modulo p: A377172 (a=3), A377175 (a=5), A377177 (a=7), A377179 (a=9).
Sequence in context: A287615 A129919 A045454 * A356833 A166575 A265808
KEYWORD
nonn,easy
AUTHOR
Jianing Song, Oct 18 2024
STATUS
approved