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A049589
Primes p such that x^57 = 2 has a solution mod p.
2
2, 3, 5, 11, 17, 23, 29, 31, 41, 43, 47, 53, 59, 71, 83, 89, 101, 107, 109, 113, 127, 131, 137, 149, 157, 167, 173, 179, 197, 223, 227, 233, 239, 251, 257, 263, 269, 277, 281, 283, 293, 307, 311, 317, 347, 353, 359, 383, 389, 397, 401, 431, 433, 439, 443, 449
OFFSET
1,1
COMMENTS
Complement of A059643 relative to A000040. - Vincenzo Librandi, Sep 14 2012
MATHEMATICA
ok[p_] := Reduce[Mod[x^57 - 2, p] == 0, x, Integers] == True; Select[Prime[Range[100]], ok] (* Vincenzo Librandi, Sep 14 2012 *)
PROG
(Magma) [p: p in PrimesUpTo(500) | exists(t){x : x in ResidueClassRing(p) | x^57 eq 2}]; // Vincenzo Librandi, Sep 14 2012
(PARI)
N=10^4; default(primelimit, N);
ok(p, r, k)={ return ( (p==r) || (Mod(r, p)^((p-1)/gcd(k, p-1))==1) ); }
forprime(p=2, N, if (ok(p, 2, 57), print1(p, ", ")));
/* Joerg Arndt, Sep 21 2012 */
CROSSREFS
Sequence in context: A154755 A040095 A040028 * A049583 A049596 A049571
KEYWORD
nonn,easy
STATUS
approved