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 A241571 #11 Sep 08 2022 08:46:07 %S A241571 0,3,5,6,9,10,12,15,17,18,20,21,24,25,27,30,31,33,35,36,38,39,40,42, %T A241571 45,48,50,51,52,53,54,55,57,59,60,63,64,65,66,69,70,72,73,75,77,78,80, %U A241571 81,84,85,86,87,90,93,94,95,96,97,99,100,101,102,103,105,108 %N A241571 Numbers n such that 2*n+15 is not a prime. %H A241571 Vincenzo Librandi, <a href="/A241571/b241571.txt">Table of n, a(n) for n = 1..1000</a> %t A241571 Select[Range[0, 200], !PrimeQ[2 # + 15] &] %o A241571 (Magma) [n: n in [0..200] | not IsPrime(2*n+15)]; %Y A241571 Complement of A089559. %Y A241571 Cf. similar sequence listed in A153144. %K A241571 nonn,easy %O A241571 1,2 %A A241571 _Vincenzo Librandi_, Apr 27 2014