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 A216423 #15 Jul 12 2018 11:26:04 %S A216423 0,6,12,3804,8346,15528,147036 %N A216423 Numbers k such that 4^k + k^4 + 1 is prime. %C A216423 a(8) > 2*10^5. - _Robert Price_, Apr 29 2014 %C A216423 a(1)-a(3) are trivially prime. a(4)-a(7) are probable primes. - _Robert Price_, May 07 2014 %t A216423 Select[Range[0, 5000], PrimeQ[4^# + #^4 + 1] &] %o A216423 (PARI) is(n)=ispseudoprime(4^n+n^4+1) \\ _Charles R Greathouse IV_, Jun 06 2017 %Y A216423 Cf. A100357, A215434-A215446, A216375. %K A216423 nonn %O A216423 1,2 %A A216423 _Vincenzo Librandi_, Sep 07 2012 %E A216423 a(5)-a(7) from _Robert Price_, Apr 29 2014