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A040038
Primes p such that x^3 = 3 has no solution mod p.
3
7, 13, 19, 31, 37, 43, 79, 97, 109, 127, 139, 157, 163, 181, 199, 211, 223, 229, 241, 277, 283, 313, 331, 337, 349, 373, 379, 397, 409, 421, 433, 457, 463, 487, 541, 571, 601, 607, 631, 673, 691, 709, 733, 739
OFFSET
1,1
COMMENTS
Primes of the form 7x^2+3xy+9y^2, whose discriminant is -243. - T. D. Noe, May 17 2005
Complement of A040036 relative to A000040. - Vincenzo Librandi, Sep 17 2012
LINKS
MATHEMATICA
ok[p_]:= Reduce[Mod[x^3 - 3, p] == 0, x, Integers] == False; Select[Prime[Range[200]], ok] (* Vincenzo Librandi, Sep 17 2012 *)
PROG
(Magma) [p: p in PrimesUpTo(1000) | not exists{x : x in ResidueClassRing(p) | x^3 eq 3} ]; // Vincenzo Librandi, Sep 17 2012
(PARI) forprime(p=2, 10^3, if(#polrootsmod(x^3-3, p)==0, print1(p, ", "))) \\ Joerg Arndt, Jul 16 2015
CROSSREFS
Sequence in context: A040079 A038160 A106870 * A081765 A257002 A216567
KEYWORD
nonn,easy
AUTHOR
STATUS
approved