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A038898 Primes p such that 23 is not a square mod p. 2
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 (list; graph; refs; listen; history; text; internal format)
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 * A297175 A089133 A103149

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

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Last modified December 14 05:36 EST 2019. Contains 329978 sequences. (Running on oeis4.)