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 A167795 #7 Jan 04 2025 00:35:21 %S A167795 2,4,5,10,11,13,17,22,23,26,34,41,46,61,67,71,79,82,89,97,101,107,121, %T A167795 122,127,134,142,151,158,163,169,173,178,179,194,202,211,214,229,239, %U A167795 241,242,254,257,263,269,289,293,302,326,338,346,347,349,358,359,379 %N A167795 Numbers with primitive root 7. %H A167795 Vincenzo Librandi, <a href="/A167795/b167795.txt">Table of n, a(n) for n = 1..1000</a> %t A167795 pr=7; Select[Range[2,2000], MultiplicativeOrder[pr,# ] == EulerPhi[ # ] &] %o A167795 (PARI) is(n)=if(n%7==0, return(0)); my(p=eulerphi(n)); znorder(Mod(7, n), p)==p \\ _Charles R Greathouse IV_, Jan 04 2025 %Y A167795 Cf. A019337 (primes with primitive root 7) %K A167795 nonn %O A167795 1,1 %A A167795 _T. D. Noe_, Nov 12 2009