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 A216422 #14 Jul 12 2018 11:36:46 %S A216422 1,17,145,427,4327,14195 %N A216422 Numbers k such that 19^k + k^19 - 1 is prime. %C A216422 a(7) > 10^5. - _Robert Price_, Mar 25 2014 %t A216422 Select[Range[0, 5000], PrimeQ[19^# + #^19 - 1] &] %o A216422 (PARI) is(n)=ispseudoprime(19^n+n^19-1) \\ _Charles R Greathouse IV_, Jun 13 2017 %Y A216422 Cf. A100357, A215434-A215446, A216375. %K A216422 nonn,hard,more %O A216422 1,2 %A A216422 _Vincenzo Librandi_, Sep 07 2012 %E A216422 a(6) from _Robert Price_, Mar 25 2014