A240102 Numbers with primitive root -18.

5, 7, 23, 29, 31, 37, 47, 53, 61, 71, 101, 103, 109, 127, 149, 151, 157, 167, 173, 181, 191, 197, 223, 239, 263, 269, 271, 277, 293, 317, 349, 359, 367, 383, 389, 397, 421, 461, 479, 503, 509, 529, 541, 557, 607, 613, 647, 653, 661, 677, 701, 719, 733

Offset

1,1

Links

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

Mathematica

pr = -18; Select[Range[2, 800], MultiplicativeOrder[pr, #] == EulerPhi[#] &]

Prog

(PARI) is(n)=if(gcd(n, 6)>1, return(0)); my(p=eulerphi(n)); znorder(Mod(-18, n), p)==p \\ Charles R Greathouse IV, Nov 26 2014

Crossrefs

Cf. numbers with positive primitive root r: A167791 (r=2), A167792 (r=3), A167793 (r=5), A167794 (r=6), A167795 (r=7), A167796 (r=8), A167797 (r=10), A240028 (r=11), A240030 (r=12), A240032 (r=13), A240094 (r=14), A240096 (r=15), A240101 (r=17), A240103 (r=18).

Cf. numbers with negative primitive root r: A167798 (r=-2), A167799 (r=-3), A167800 (r=-4), A167801 (r=-5), A167802 (r=-6), A167803 (r=-7), A167804 (r=-8), A167805 (r=-9), A167806 (r=-10), A240029 (r=-11), A240031 (r=-12), A240093 (r=-13), A240095 (r=-14), A240097 (r=-15), A240100 (r=-17).

Sequence in context: A294154 A260658 A028281 * A105890 A329625 A018656

Adjacent sequences: A240099 A240100 A240101 * A240103 A240104 A240105

Keyword

nonn,easy

Author

Vincenzo Librandi, Apr 01 2014

Status

approved