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 A050505 #26 Oct 27 2023 22:00:44
%S A050505 2,4,5,6,8,10,11,12,14,16,17,18,19,20,22,23,24,26,27,28,29,30,32,34,
%T A050505 35,36,38,39,40,41,42,44,45,46,47,48,50,52,53,54,55,56,57,58,59,60,61,
%U A050505 62,64,65,66,68,70,71,72,74,76,77,78,80,81,82,83,84,85,86,88,89,90,91,92
%N A050505 Unlucky numbers.
%C A050505 A145649(a(n)) = 0; complement of A000959. - _Reinhard Zumkeller_, Oct 15 2008
%H A050505 Michael De Vlieger, <a href="/A050505/b050505.txt">Table of n, a(n) for n = 1..10000</a>
%F A050505 Numbers deleted in creating the lucky numbers, numbers not in A000959.
%t A050505 L = Table[2 i + 1, {i, 0, 50}]; For[n = 2, n < Length[L], r = L[[n++]]; L = ReplacePart[L, Table[r i -> Nothing, {i, 1, Length[L]/r}]]]; Complement[Range@ Max@ L, L] (* _Michael De Vlieger_, Feb 25 2017, after _Jean-François Alcover_ at A000959 *)
%Y A050505 Cf. A000959.
%K A050505 nonn,easy
%O A050505 1,1
%A A050505 _Asher Auel_, Dec 16 1999