A038928 - OEIS

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A038928

Primes p such that 47 is not a square mod p.

3, 5, 7, 13, 29, 41, 59, 71, 73, 79, 83, 103, 109, 113, 131, 137, 181, 191, 193, 229, 233, 239, 251, 257, 263, 271, 281, 283, 293, 307, 313, 317, 331, 347, 349, 373, 379, 383, 389, 409, 421, 431, 433, 439, 449

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OFFSET

1,1

COMMENTS

Also, only entries p=1 (mod 4) of the sequence are not squares mod 47 (from the quadratic reciprocity law). - Lekraj Beedassy, Jul 21 2004

LINKS

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

MATHEMATICA

Select[Prime@Range[120], JacobiSymbol[47, #] == -1 &] (* Vincenzo Librandi, Sep 09 2012 *)

PROG

(PARI) select(n->!issquare(Mod(47, n)), primes(100)) \\ Charles R Greathouse IV, Sep 09 2012

CROSSREFS