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 A325443 #4 May 02 2019 16:04:20
%S A325443 3,6,7,9,12,15,19,21,24,25,27,30,31,33,35,39,42,43,45,48,51,54,55,57,
%T A325443 60,63,66,67,69,71,73,75,78,79,81,84,87,91,93,96,97,99,102,103,105,
%U A325443 108,111,114,115,117,120,121,123,127,129,132,135,138,139,141,143
%N A325443 Complement of A325442.
%C A325443 These are the numbers 2x-1 and 3x as x ranges through the numbers x>1 in A325442.
%H A325443 Clark Kimberling, <a href="/A325443/b325443.txt">Table of n, a(n) for n = 1..10000</a>
%t A325443 a = {1}; Do[AppendTo[a, NestWhile[# + 1 &, Last[a] + 1, Apply[Or,
%t A325443 Map[MemberQ[a, #] &, Select[Flatten[{(#+1)/2, #/3}],
%t A325443 IntegerQ]]] &]], {150}]; a (* A325442 *)
%t A325443 Complement[Range[Last[a]], a] (* A325443 *)
%t A325443 (* _Peter J. C. Moses_, Apr 25 2019 *)
%Y A325443 Cf. A325417, A325442.
%K A325443 nonn,easy
%O A325443 1,1
%A A325443 _Clark Kimberling_, May 02 2019