OFFSET
1,1
COMMENTS
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
KEYWORD
nonn,easy
AUTHOR
Vincenzo Librandi, Sep 19 2012
STATUS
approved