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A049552 Primes p such that x^20 = 2 has a solution mod p. 2
2, 7, 23, 47, 73, 79, 89, 103, 113, 127, 151, 167, 199, 223, 233, 239, 257, 263, 337, 353, 359, 367, 383, 431, 439, 463, 479, 487, 503, 577, 593, 599, 607, 617, 647, 719, 727, 743, 823, 839, 863, 887, 911, 919, 937, 967, 983, 1033, 1039, 1049, 1063, 1087 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Complement of A059309 relative to A000040. - Vincenzo Librandi, Sep 13 2012

LINKS

R. J. Mathar, Table of n, a(n) for n = 1..1000

Index entries for related sequences

MATHEMATICA

ok[p_]:= Reduce[Mod[x^20 - 2, p] == 0, x, Integers] =!= False; Select[Prime[Range[200]], ok] (* Vincenzo Librandi, Sep 13 2012 *)

PROG

(MAGMA) [p: p in PrimesUpTo(1100) | exists(t){x : x in ResidueClassRing(p) | x^20 eq 2}]; // Vincenzo Librandi, Sep 13 2012

CROSSREFS

Cf. A000040, A059309.

Sequence in context: A089176 A049232 A100917 * A049572 A094786 A028871

Adjacent sequences:  A049549 A049550 A049551 * A049553 A049554 A049555

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane

STATUS

approved

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Last modified September 25 06:32 EDT 2020. Contains 337335 sequences. (Running on oeis4.)