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 A247963 #26 Sep 08 2022 08:46:10 %S A247963 0,1,2,4,5,54,81,310,360,1117,1410,3320,66162 %N A247963 Numbers n such that 57^n + 2 is prime. %C A247963 Numbers of the form 4*h+3 are not in the sequence, since in this case 57^n+2 is divisible by 5. %C A247963 Numbers ending with 6 are not in the sequence, since in this case 57^n+2 is divisible by 11. %C A247963 If n == 10 mod 16, 57^n+2 is divisible by 17. - _Derek Orr_, Oct 04 2014 %C A247963 a(14) > 2*10^5. - _Robert Price_, Jun 11 2015 %H A247963 Henri & Renaud Lifchitz, <a href="http://www.primenumbers.net/prptop/searchform.php?form=57%5En%2B2&action=Search">PRP Top Records: Search for 57^n+2</a>. %t A247963 Select[Range[0, 2000], PrimeQ[57^# + 2] &] %o A247963 (Magma) [n: n in [0..300]| IsPrime( 57^n + 2 )]; %o A247963 (PARI) for(n=1,10^3,if(ispseudoprime(57^n+2),print1(n,", "))) \\ _Derek Orr_, Oct 04 2014 %Y A247963 Cf. similar sequences listed in A247957. %K A247963 nonn,more %O A247963 1,3 %A A247963 _Vincenzo Librandi_, Oct 03 2014 %E A247963 Edited by _Bruno Berselli_, Oct 04 2014 %E A247963 a(13) from _Robert Price_, Jun 11 2015