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 A187805 #10 Feb 17 2017 17:00:03 %S A187805 3,53,83,487,743 %N A187805 Numbers n such that (7^n + 6^n)/13 is prime. %C A187805 All terms are prime. %C A187805 a(6) > 10^5 %t A187805 Select[ Prime[ Range[100000] ], PrimeQ[ (7^# + 6^#)/13 ]& ] %o A187805 (PARI) is(n)=ispseudoprime((7^n+6^n)/13) \\ _Charles R Greathouse IV_, Feb 17 2017 %Y A187805 Cf. A181141, A128336, A128337. %K A187805 more,hard,nonn %O A187805 1,1 %A A187805 _Robert Price_, Jan 06 2013