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A040087 Primes p such that x^3 = 21 has a solution mod p. 2
2, 3, 5, 7, 11, 13, 17, 23, 29, 41, 43, 47, 53, 59, 71, 73, 79, 83, 89, 101, 107, 113, 131, 137, 149, 163, 167, 173, 179, 191, 197, 227, 229, 233, 239, 241, 251, 257, 263, 269, 277, 281, 283, 293, 311, 317, 347, 349 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Complement of A040088 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 - 21, 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 21}]; // Vincenzo Librandi, Sep 11 2012

CROSSREFS

Cf. A000040, A040088.

Sequence in context: A192503 A040067 A181659 * A040065 A051647 A042986

Adjacent sequences:  A040084 A040085 A040086 * A040088 A040089 A040090

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane.

STATUS

approved

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Last modified May 24 06:53 EDT 2019. Contains 323529 sequences. (Running on oeis4.)