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A019353
Primes with primitive root 27.
2
2, 5, 17, 29, 53, 89, 101, 113, 137, 149, 173, 197, 233, 257, 269, 281, 293, 317, 353, 389, 401, 449, 461, 509, 521, 557, 569, 593, 617, 641, 653, 677, 701, 773, 797, 809, 821, 857, 881, 929, 941, 953, 977, 1013, 1049, 1061, 1097, 1109, 1193, 1217, 1229, 1277, 1301
OFFSET
1,1
COMMENTS
From Jianing Song, May 12 2024: (Start)
Members of A019334 that are not congruent to 1 mod 3. Terms greater than 2 are congruent to 5 modulo 12.
According to Artin's conjecture, the number of terms <= N is roughly ((3/5)*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). (End)
MATHEMATICA
pr=27; Select[Prime[Range[300]], MultiplicativeOrder[pr, # ] == #-1 &]
PROG
(PARI) isA019353(n) = isprime(n) && (n!=3) && znorder(Mod(27, n)) == n-1 \\ Jianing Song, May 12 2024
CROSSREFS
KEYWORD
nonn
STATUS
approved