A038892 Primes p such that 19 is not a square mod p.

2, 7, 11, 13, 23, 29, 37, 41, 43, 47, 53, 83, 89, 97, 109, 113, 131, 139, 163, 173, 181, 191, 193, 199, 239, 241, 251, 257, 263, 269, 271, 281, 283, 293, 311, 317, 337, 347, 359, 367, 373, 401, 409, 419, 421, 433

Offset: 1

Author

N. J. A. Sloane

Keywords

• nonn

Comments

Also, only entries p=1 (mod 4) of the sequence are not squares mod 19 (from the quadratic reciprocity law). - Lekraj Beedassy, Jul 21 2004

Links

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

Crossrefs

Cf. A297176

Programs

Mathematica

Select[Prime@Range[120], JacobiSymbol[19, #] == -1 &] (* Vincenzo Librandi, Sep 08 2012 *)

Extensions

Offset changed from 0 to 1 by Vincenzo Librandi, Sep 08 2012