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 A125000 #14 Oct 08 2018 18:14:31 %S A125000 1,17,2873,10081,3345113,420048673,449349533,2961432773,19723772249, %T A125000 821451792317,1207046362769 %N A125000 Integers n such that 2^n == 19 (mod n). %C A125000 No other terms below 10^15. Some larger terms: 500796684074966733196301. - _Max Alekseyev_, May 23 2012 %t A125000 m = 19; Join[Select[Range[m], Divisible[2^# - m, #] &], %t A125000 Select[Range[m + 1, 10^6], PowerMod[2, #, #] == m &]] (* _Robert Price_, Oct 08 2018 *) %Y A125000 Cf. A124974, A033981, A050259, A124977, A124965, A015911, A015910. %K A125000 nonn,more %O A125000 1,2 %A A125000 _Zak Seidov_, Nov 15 2006 %E A125000 Terms 1, 17 prepended by _Max Alekseyev_, May 20 2011 %E A125000 a(8)-a(11) from _Max Alekseyev_, May 23 2012