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 A269227 #13 Sep 08 2022 08:46:15 %S A269227 0,1,4,5,12,16,27,87,252,1052,1691,3237,3669,16140,17072,27932,70811 %N A269227 Numbers n such that 7^n + 6^(n + 1) is prime. %C A269227 a(18) > 10^5. %t A269227 Select[Range[0,100000], PrimeQ[7^# + 6^(# + 1)] &] %o A269227 (Magma) [n: n in [0..500] | IsPrime(7^n+6^(n+1))]; // _Vincenzo Librandi_, Jul 12 2016 %o A269227 (PARI) is(n)=ispseudoprime(7^n+6^(n+1)) \\ _Charles R Greathouse IV_, Jun 13 2017 %Y A269227 Cf. A093765. %K A269227 nonn,more %O A269227 1,3 %A A269227 _Robert Price_, Jul 11 2016