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 A125957 #11 Feb 20 2017 14:51:15
%S A125957 3,5,17,67,83,101,1373,6101,12119,61781
%N A125957 Numbers n such that (2^n + 11^n)/13 is prime.
%C A125957 All terms are primes. Corresponding primes of the form (2^n + 11^n)/13 are {103, 12391, 38880540653801911, ...}.
%C A125957 a(11) > 10^5. - _Robert Price_, Feb 26 2013
%t A125957 Do[p=Prime[n];f=(2^p+11^p)/13; If[PrimeQ[f], Print[{p, f}]], {n, 1, 100}]
%o A125957 (PARI) is(n)=ispseudoprime((2^n+11^n)/13) \\ _Charles R Greathouse IV_, Feb 20 2017
%Y A125957 Cf. A000978 = numbers n such that (2^n + 1)/3 is prime. Cf. A057469 = numbers n such that (2^n + 3^n)/5 is prime. Cf. A082387 = numbers n such that (2^n + 5^n)/7 is prime.
%K A125957 hard,more,nonn
%O A125957 1,1
%A A125957 _Alexander Adamchuk_, Feb 06 2007
%E A125957 2 more terms from _Ryan Propper_, Feb 09 2008
%E A125957 a(9)-a(10) from _Robert Price_, Feb 26 2013