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 A019341 #16 Sep 26 2020 11:57:51
%S A019341 2,5,11,19,31,37,41,47,59,67,71,73,83,89,97,109,137,149,151,167,197,
%T A019341 227,239,241,281,293,307,317,349,353,359,379,383,397,401,431,449,457,
%U A019341 479,487,509,541,557,577,587,593,613,617,631,643,683,691,733,743,769,773,787,811
%N A019341 Primes with primitive root 13.
%H A019341 Vincenzo Librandi, <a href="/A019341/b019341.txt">Table of n, a(n) for n = 1..1000</a>
%H A019341 <a href="/index/Pri#primes_root">Index entries for primes by primitive root</a>
%t A019341 pr=13; Select[Prime[Range[200]], MultiplicativeOrder[pr, # ] == #-1 &]
%t A019341 Join[{2,5,11},Select[Prime[Range[200]],PrimitiveRoot[#,13]==13&]] (* _Harvey P. Dale_, Sep 26 2020 *)
%K A019341 nonn
%O A019341 1,1
%A A019341 _David W. Wilson_