%I #12 Apr 19 2023 16:02:11
%S 2,5,10,11,19,22,25,31,37,38,41,47,50,59,62,67,71,73,74,82,83,89,94,
%T 97,109,118,121,125,134,137,142,146,149,151,166,167,178,194,197,218,
%U 227,239,241,242,250,274,281,293,298,302,307,317,334,349,353,359,361
%N Numbers with primitive root 13.
%H Vincenzo Librandi, <a href="/A240032/b240032.txt">Table of n, a(n) for n = 1..1000</a>
%t pr = 13; Select[Range[2, 600], MultiplicativeOrder[pr, #] == EulerPhi[#] &]
%t Join[{2,5,10,11},Select[Range[400],MemberQ[PrimitiveRootList[#],13]&]] (* _Harvey P. Dale_, Apr 19 2023 *)
%Y 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).
%Y 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).
%K nonn,easy
%O 1,1
%A _Vincenzo Librandi_, Apr 01 2014