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 A167793 #7 Jan 04 2025 00:36:49 %S A167793 2,3,6,7,9,14,17,18,23,27,34,37,43,46,47,49,53,54,73,74,81,83,86,94, %T A167793 97,98,103,106,107,113,137,146,157,162,166,167,173,193,194,197,206, %U A167793 214,223,226,227,233,243,257,263,274,277,283,289,293,307,314,317,334,343,346 %N A167793 Numbers with primitive root 5. %H A167793 Vincenzo Librandi, <a href="/A167793/b167793.txt">Table of n, a(n) for n = 1..1000</a> %t A167793 pr=5; Select[Range[2,2000], MultiplicativeOrder[pr,# ] == EulerPhi[ # ] &] %o A167793 (PARI) is(n)=if(n%5==0, return(0)); my(p=eulerphi(n)); znorder(Mod(5, n), p)==p \\ _Charles R Greathouse IV_, Jan 04 2025 %Y A167793 Cf. A019335 (primes with primitive root 5) %K A167793 nonn %O A167793 1,1 %A A167793 _T. D. Noe_, Nov 12 2009