This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A240030 #10 Apr 01 2014 05:21:40 %S A240030 5,7,17,25,31,41,43,49,53,67,101,103,113,125,127,137,139,149,151,163, %T A240030 173,197,223,257,269,281,283,289,293,317,343,353,367,379,389,401,449, %U A240030 461,509,523,547,557,569,571,593,607,617,619,625,631,641,653,691 %N A240030 Numbers with primitive root 12. %H A240030 Vincenzo Librandi, <a href="/A240030/b240030.txt">Table of n, a(n) for n = 1..1000</a> %t A240030 pr = 12; Select[Range[2, 700], MultiplicativeOrder[pr, #] == EulerPhi[#] &] %Y A240030 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). %Y A240030 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). %K A240030 nonn,easy %O A240030 1,1 %A A240030 _Vincenzo Librandi_, Apr 01 2014