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 A217385 #17 Jun 13 2017 14:26:06 %S A217385 1,2,4,7,10,19,22,44,62,76,122,2191,3134,9244,40999,48230 %N A217385 Numbers n such that 9^n + 8 is prime. %C A217385 Contains exactly the halved even terms of A217136. - _Bruno Berselli_, Oct 04 2012 %t A217385 Select[Range[5000], PrimeQ[9^# + 8] &] %o A217385 (PARI) is(n)=ispseudoprime(9^n+8) \\ _Charles R Greathouse IV_, Jun 13 2017 %Y A217385 Cf. A090649, A177093, A217136, A217384. %K A217385 nonn,hard,more %O A217385 1,2 %A A217385 _Vincenzo Librandi_, Oct 04 2012 %E A217385 a(14) from _Bruno Berselli_, Oct 05 2012 %E A217385 a(15)-a(16) derived from A217136 by _Robert Price_, May 19 2015