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A038880 Primes p such that 10 is not a square mod p. 2
7, 11, 17, 19, 23, 29, 47, 59, 61, 73, 97, 101, 103, 109, 113, 127, 131, 137, 139, 149, 167, 179, 181, 193, 211, 223, 229, 233, 251, 257, 263, 269, 313, 331, 337, 349, 353, 367, 379, 383, 389, 419, 421, 433, 457, 461, 463, 487, 491, 499, 503, 509, 541, 571 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Inert rational primes in the field Q(sqrt(10)).- N. J. A. Sloane, Dec 26 2017

Also primes p such that p divides 5^(p-1)/2 + 2^(p-1)/2. - Cino Hilliard, Sep 06 2004

All primes p such that (p^2 - 1)/24 mod 10 = {2,5}. - Richard R. Forberg, Aug 31 2013

Primes that are 7, 11, 17, 19, 21, 23, 29, or 33 mod 40. - Charles R Greathouse IV, Mar 18 2018

LINKS

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

Index to sequences related to decomposition of primes in quadratic fields

FORMULA

a(n) ~ 2n log n. - Charles R Greathouse IV, Mar 18 2018

MATHEMATICA

Select[ Prime@Range[2, 105], JacobiSymbol[10, # ] == -1 &] (* Robert G. Wilson v *)

PROG

(PARI) list(lim)=my(v=List()); forprime(p=7, lim, if(kronecker(10, p)<0, listput(v, p))); Vec(v) \\ Charles R Greathouse IV, Mar 18 2018

CROSSREFS

Cf. A007348.

Sequence in context: A034849 A269256 A106070 * A019365 A191055 A078497

Adjacent sequences:  A038877 A038878 A038879 * A038881 A038882 A038883

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane.

EXTENSIONS

More terms from Robert G. Wilson v, Dec 15 2005

STATUS

approved

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Last modified November 19 08:40 EST 2018. Contains 317347 sequences. (Running on oeis4.)