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 A128460 #23 Sep 08 2022 08:45:30 %S A128460 1,2,3,13,14,19,20,23,38,1124,7592,11755,12155,12915,14172,15500, %T A128460 20255,28388,184650 %N A128460 Numbers k such that 19^k - 2 is a prime. %C A128460 No more terms through 50000. - _Ryan Propper_, Dec 04 2008 %C A128460 a(20) > 2*10^5. - _Robert Price_, Oct 22 2014 %t A128460 Do[ f = 19^n - 2; If[ PrimeQ[ f ], Print[ {n, f} ] ], {n,1,1000} ] %o A128460 (Magma) [n: n in [0..1000] | IsPrime(19^n-2)]; // _Vincenzo Librandi_, Oct 23 2014 %Y A128460 Cf. A084714 (smallest prime of the form (2n-1)^k - 2). %Y A128460 Cf. A128472 (smallest prime of the form (2n-1)^k - 2 for k > (2n-1)). %Y A128460 Cf. A014224, A109080, A090669, A128455, A128457, A128458, A128459, A128461. %K A128460 nonn,hard,more %O A128460 1,2 %A A128460 _Alexander Adamchuk_, Mar 14 2007 %E A128460 1124 from _Stefan Steinerberger_, May 05 2007 %E A128460 7592 from _Ryan Propper_, Dec 31 2007 %E A128460 Additional terms from _Ryan Propper_, Dec 04 2008 %E A128460 a(19) from _Robert Price_, Oct 22 2014