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A040984 Primes p such that x^23 = 2 has no solution mod p. 16
47, 139, 277, 461, 599, 691, 829, 967, 1013, 1151, 1289, 1381, 1427, 1657, 1933, 1979, 2347, 2393, 2531, 3037, 3083, 3221, 3313, 3359, 3727, 3911, 4003, 4049, 4463, 4831, 4877, 4969, 5107, 5521, 5659, 5843, 5981, 6073, 6211, 6257, 6763, 6947, 7039, 7177 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Contribution from Charles R Greathouse IV, Sep 12 2012: (Start)
Complement of A049555 relative to A000040.
Terms of A212374 which are not in this sequence: 5153, 18539, 20747, 49681, 51199, 51797, 55201, 70381, .... (End)
LINKS
MATHEMATICA
Select[Prime[Range[PrimePi[7200]]], ! MemberQ[PowerMod[Range[#], 23, #], Mod[2, #]] &] (* T. D. Noe, Sep 13 2012 *)
ok[p_]:=Reduce[Mod[x^23 - 2, p]==0, x, Integers]==False; Select[Prime[Range[25000]], ok] (* Vincenzo Librandi, Sep 13 2012 *)
PROG
(Magma) [p: p in PrimesUpTo(8000) | forall{x: x in ResidueClassRing(p) | x^23 ne 2}]; // Vincenzo Librandi, Aug 21 2012
(PARI) select(n->!ispower(Mod(2, n), 23), primes(1000)) \\ Charles R Greathouse IV, Sep 12 2012
CROSSREFS
Cf. A212374.
Sequence in context: A355727 A062637 A212374 * A136070 A055822 A044379
KEYWORD
nonn,easy
AUTHOR
Klaus Brockhaus, Jan 20 2001
STATUS
approved

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Last modified February 23 23:47 EST 2024. Contains 370288 sequences. (Running on oeis4.)