close
login
A049596
Primes p such that x^9 = 2 has a solution mod p.
6
2, 3, 5, 11, 17, 23, 29, 31, 41, 43, 47, 53, 59, 71, 83, 89, 101, 107, 113, 127, 131, 137, 149, 157, 167, 173, 179, 191, 197, 223, 227, 229, 233, 239, 251, 257, 263, 269, 277, 281, 283, 293, 311, 317, 347, 353, 359, 383, 389, 397, 401, 419, 431, 439, 443, 449
OFFSET
1,1
COMMENTS
Coincides with sequence of "primes p such that x^27 = 2 has a solution mod p" for first 339 terms, then diverges.
Complement of A059262 relative to A000040. - Vincenzo Librandi, Sep 15 2012
EXAMPLE
0^9 == 2 (mod 2). 2^9 == 2 (mod 3). 2^9 == 2 (mod 5). 6^9 == 2 (mod 11). 2^9 == 2 (mod 17). 9^9 == 2 (mod 23). 11^9 == 2 (mod 29). 16^9 == 2 (mod 31). 20^9 == 2 (mod 41). 26^9 == 2 (mod 43). - R. J. Mathar, Jul 20 2025
MATHEMATICA
ok[p_]:= Reduce[Mod[x^9 - 2, p] == 0, x, Integers] =!= False; Select[Prime[Range[100]], ok] (* Vincenzo Librandi, Sep 15 2012 *)
PROG
(Magma) [p: p in PrimesUpTo(500) | exists(t){x : x in ResidueClassRing(p) | x^9 eq 2}]; // Vincenzo Librandi, Sep 15 2012
CROSSREFS
KEYWORD
nonn,easy
STATUS
approved