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A240107
Numbers with primitive root -20.
2
11, 13, 17, 31, 37, 53, 59, 73, 79, 113, 121, 131, 137, 139, 157, 169, 173, 179, 191, 199, 211, 233, 239, 257, 271, 277, 289, 293, 313, 317, 331, 337, 353, 359, 379, 397, 419, 431, 433, 439, 479, 499, 557, 593, 599, 613, 631, 653, 659, 673, 677, 719, 751
OFFSET
1,1
LINKS
MATHEMATICA
pr = -20; Select[Range[2, 800], MultiplicativeOrder[pr, #] == EulerPhi[#] &]
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), A240100 (r=17), A240103 (r=18), A240106 (r=19), A240108 (r=20).
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), A240102 (r=-18), A240104 (r=-19).
Sequence in context: A335976 A052031 A166009 * A105892 A111337 A359136
KEYWORD
nonn,easy
AUTHOR
Vincenzo Librandi, Apr 01 2014
STATUS
approved