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A040085 Primes p such that x^3 = 20 has a solution mod p. 2
2, 3, 5, 7, 11, 17, 19, 23, 29, 41, 47, 53, 59, 61, 71, 83, 89, 97, 101, 107, 113, 127, 131, 137, 149, 151, 167, 173, 179, 191, 193, 197, 227, 233, 239, 251, 257, 263, 269, 281, 293, 311, 317, 347, 353, 359, 373 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Complement of A040086 relative to A000040. - Vincenzo Librandi, Sep 13 2012

LINKS

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

MATHEMATICA

ok [p_]:=Reduce[Mod[x^3 - 20, p] == 0, x, Integers] =!= False;  Select[Prime[Range[180]], ok] (* Vincenzo Librandi, Sep 11 2012 *)

PROG

(MAGMA) [p: p in PrimesUpTo(450) | exists(t){x : x in ResidueClassRing(p) | x^3 eq 20}]; // Vincenzo Librandi, Sep 11 2012

CROSSREFS

Cf. A000040, A040086.

Sequence in context: A301590 A293194 A162566 * A040049 A092787 A181562

Adjacent sequences:  A040082 A040083 A040084 * A040086 A040087 A040088

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane.

STATUS

approved

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Last modified May 10 14:32 EDT 2021. Contains 343771 sequences. (Running on oeis4.)