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A038905 31 is a square mod p. 1
2, 3, 5, 11, 23, 31, 41, 43, 79, 83, 97, 101, 109, 113, 127, 139, 149, 151, 157, 167, 173, 179, 193, 199, 223, 233, 239, 251, 257, 263, 271, 281, 293, 317, 331, 347, 349, 367, 373, 383, 397, 421, 463, 487, 491 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Also, only entries p=1 (mod 4) of the sequence are squares mod 31 (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[100]], JacobiSymbol[31, #] != -1 &] (* Vincenzo Librandi, Sep 07 2012 *)

CROSSREFS

Sequence in context: A118571 A118504 A215714 * A019405 A079848 A237810

Adjacent sequences:  A038902 A038903 A038904 * A038906 A038907 A038908

KEYWORD

nonn

AUTHOR

N. J. A. Sloane.

STATUS

approved

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Last modified November 18 04:44 EST 2019. Contains 329248 sequences. (Running on oeis4.)