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 A137236 #18 May 10 2021 02:32:44 %S A137236 0,1,2,6,10,15,94,198,219,4543,11511,12638,45606 %N A137236 Numbers k such that 13^k + 4 is prime. %C A137236 a(14) > 10^5. - _Tyler NeSmith_, May 09 2021 %H A137236 Henri Lifchitz and Renaud Lifchitz, <a href="http://www.primenumbers.net/prptop/searchform.php?form=13%5En%2B4">PRP Records</a>. %o A137236 (PARI) for(n=0,300,if(isprime(13^n+4),print1(n","))) %K A137236 hard,more,nonn %O A137236 1,3 %A A137236 _Jason Earls_, Mar 08 2008 %E A137236 a(13) from Lelio R. Paula contributed by _Iain Fox_, Nov 24 2017