A216881 Primes p such that x^7 = 3 has a solution mod p.

2, 3, 5, 7, 11, 13, 17, 19, 23, 31, 37, 41, 47, 53, 59, 61, 67, 73, 79, 83, 89, 97, 101, 103, 107, 109, 131, 137, 139, 149, 151, 157, 163, 167, 173, 179, 181, 191, 193, 199, 223, 227, 229, 233, 241, 251, 257, 263, 269, 271, 277, 283, 293, 307, 311, 313, 317

Offset

1,1

Comments

Complement of A042969 relative to A000040.

Differs from A042966 first at index 98. - R. J. Mathar, Mar 13 2013

Links

Vincenzo Librandi, Table of n, a(n) for n = 1..1000

Mathematica

ok[p_] := Reduce[Mod[x^7 - 3, p] == 0, x, Integers] =!= False; Select[Prime[Range[150]], ok]

Prog

(Magma) [p: p in PrimesUpTo(500) | exists(t){x: x in ResidueClassRing(p) | x^7 eq 3}];

Crossrefs

Sequence in context: A102348 A161929 A216882 * A042966 A128898 A006514

Adjacent sequences: A216878 A216879 A216880 * A216882 A216883 A216884

Keyword

nonn,easy

Author

Vincenzo Librandi, Sep 19 2012

Status

approved