A038875 Primes p with legendre(3,p) = -1.

2, 5, 7, 17, 19, 29, 31, 41, 43, 53, 67, 79, 89, 101, 103, 113, 127, 137, 139, 149, 151, 163, 173, 197, 199, 211, 223, 233, 257, 269, 271, 281, 283, 293, 307, 317, 331, 353, 367, 379, 389, 401, 439, 449, 461, 463, 487, 499, 509, 521, 523, 547, 557, 569, 571, 593

Offset: 1

Author

N. J. A. Sloane

Keywords

• nonn

Comments

Apart from the first term, primes p such that 3 is not a square mod p.

Apart from the first term, identical to A003630.

Links

• Vincenzo Librandi, Table of n, a(n) for n = 1..1000

Crossrefs

Cf. A040117, A003630.

Programs

Mathematica

Select[Prime@Range[120], JacobiSymbol[3, #] == -1 &] (* Vincenzo Librandi, Sep 09 2012 *)

PARI

isok(p) = isprime(p) && (kronecker(3, p) == -1); \\ Michel Marcus, Jan 24 2023

Extensions

Edited by D. S. McNeil, R. J. Mathar and N. J. A. Sloane, Aug 15 2010