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 A217352 #28 Oct 27 2024 13:02:55 %S A217352 2,4,6,8,9,10,15,20,46,49,61,98,110,144,266,344,978,1692,1880,1924, %T A217352 3142,3220,4209,5708,7064,13465,13858,19474,22666,26807 %N A217352 Numbers k such that 6^k - 7 is prime. %C A217352 a(31) > 50000. - _Michael S. Branicky_, Oct 27 2024 %t A217352 Select[Range[10000], PrimeQ[6^# - 7] &] %o A217352 (PARI) is(n)=ispseudoprime(6^n-7) \\ _Charles R Greathouse IV_, Jun 13 2017 %Y A217352 Cf. A059614, A217351. %K A217352 nonn,more,hard %O A217352 1,1 %A A217352 _Vincenzo Librandi_, Oct 02 2012 %E A217352 a(26)-a(27) from _Michael S. Branicky_, Jan 29 2023 %E A217352 a(28)-a(29) from _Michael S. Branicky_, Apr 10 2023 %E A217352 a(30) from _Michael S. Branicky_, Oct 27 2024