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A038898

Primes p such that 23 is not a square mod p.

3, 5, 17, 31, 37, 47, 53, 59, 61, 71, 89, 97, 109, 113, 127, 131, 137, 139, 149, 151, 157, 163, 167, 179, 181, 211, 223, 229, 239, 241, 271, 281, 293, 307, 311, 313, 331, 337, 347, 373, 389, 401, 421, 433, 439

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OFFSET

1,1

COMMENTS

Inert rational primes in the field Q(sqrt(23)). - N. J. A. Sloane, Dec 26 2017

Also, only entries p == 1 (mod 4) of the sequence are not squares mod 23 (from the quadratic reciprocity law). - Lekraj Beedassy, Jul 21 2004

LINKS

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

Index to sequences related to decomposition of primes in quadratic fields

MATHEMATICA

Select[Prime@Range[120], JacobiSymbol[23, #] == -1 &] (* Vincenzo Librandi, Sep 08 2012 *)

CROSSREFS

Sequence in context: A174913 A079496 A230639 * A333353 A297175 A089133

Adjacent sequences: A038895 A038896 A038897 * A038899 A038900 A038901

KEYWORD

nonn

AUTHOR

N. J. A. Sloane

EXTENSIONS

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

STATUS

approved

URL: https://oeis.org/A038898

⇱ A038898 - OEIS