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 A128031 #20 Mar 11 2023 23:06:35 %S A128031 3,11,17,491,23029 %N A128031 Numbers k such that (17^k - 3^k)/14 is prime. %C A128031 All terms are primes. %C A128031 No other terms < 100000. %t A128031 k=14; Select[ Prime[ Range[1,200] ], PrimeQ[ ((k+3)^# - 3^#)/k ]& ] %o A128031 (PARI) is(n)=isprime((17^n-3^n)/14) \\ _Charles R Greathouse IV_, Feb 17 2017 %Y A128031 Cf. A028491 = numbers n such that (3^n - 1)/2 is prime. %Y A128031 Cf. A057468 = numbers n such that 3^n - 2^n is prime. %Y A128031 Cf. A059801 = numbers n such that 4^n - 3^n is prime. %Y A128031 Cf. A121877 = numbers n such that (5^n - 3^n)/2 is a prime. %Y A128031 Cf. A128024, A128025, A128026, A128027, A128028, A128029, A128030, A128032. %K A128031 hard,more,nonn %O A128031 1,1 %A A128031 _Alexander Adamchuk_, Feb 11 2007 %E A128031 a(5)=23029 from _Robert Price_, Nov 03 2011