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 A217353 #21 Sep 15 2024 14:31:32 %S A217353 1,2,3,4,8,50,58,71,112,1079,1318,2252,3524,4800,5560,6919,11484, %T A217353 12184,41099,94711,375460,449248 %N A217353 Numbers k such that 8^k - 3 is prime. %C A217353 3*A217353 is a subsequence of A050414. - _Bruno Berselli_, Oct 02 2012 %t A217353 Select[Range[5000], PrimeQ[8^# - 3] &] %o A217353 (PARI) is(n)=ispseudoprime(8^n-3) \\ _Charles R Greathouse IV_, May 22 2017 %Y A217353 Cf. A050414, A059266, A217354. %K A217353 nonn,more %O A217353 1,2 %A A217353 _Vincenzo Librandi_, Oct 02 2012 %E A217353 a(15)-a(17), a(19)-a(20) using A050414 by _Bruno Berselli_, Oct 02 2012 %E A217353 a(18), a(21)-a(22) using A050414 by _Michael S. Branicky_, Sep 15 2024