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 A067946 #17 Aug 15 2021 02:19:30
%S A067946 1,2,4,6,8,12,16,18,24,32,36,42,48,52,54,64,72,84,96,104,108,126,128,
%T A067946 144,156,162,168,186,192,208,216,252,256,272,288,294,312,324,336,342,
%U A067946 372,378,384,416,432,468,486,504,512,544,558,576,588,624,648,672,676
%N A067946 Numbers k that divide 5^k - 1.
%H A067946 Harvey P. Dale, <a href="/A067946/b067946.txt">Table of n, a(n) for n = 1..1000</a>
%t A067946 Join[{1},Select[Range[700],PowerMod[5,#,#]==1&]] (* _Harvey P. Dale_, Feb 25 2015 *)
%o A067946 (PARI) is(n)=Mod(5,n)^n==1 \\ _Charles R Greathouse IV_, Nov 04 2016
%Y A067946 Cf. A024049.
%K A067946 easy,nonn
%O A067946 1,2
%A A067946 _Benoit Cloitre_, Mar 05 2002