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 A049636 #16 Dec 16 2017 05:27:27
%S A049636 2,5,6,8,9,11,12,14,15,17,18,20,21,23,24,26,27,29,30,32,33,35,36,38,
%T A049636 39,41,42,44,45,47,48,50,51,53,54,56,57,59,60,62,63,65,66,68,69,71,72,
%U A049636 74,75,77,78,80,81,83,84,86,87,89,90,92,93,95,96,98,99,101,102,104,105,107,108
%N A049636 Congruent to 0 or 2 mod 3, but not equal to 0 or 3.
%C A049636 a(n) = T(n, 2), array T as in A049627.
%H A049636 G. C. Greubel, <a href="/A049636/b049636.txt">Table of n, a(n) for n = 0..1000</a>
%F A049636 O.g.f.: -(x+2)(x^2-x-1)/((1-x)^2*(1+x)). - _R. J. Mathar_, Aug 13 2008
%t A049636 Join[{2},Select[Range[4,100],MemberQ[{0,2},Mod[#,3]]&]] (* or *) With[{nn=100},Join[{2},Riffle[Range[5,nn,3],Range[6,nn,3]]]] (* _Harvey P. Dale_, Jul 14 2012 *)
%o A049636 (PARI) x='x+O('x^20); Vec(-(x+2)*(x^2-x-1)/((1-x)^2*(1+x))) \\ _G. C. Greubel_, Dec 15 2017
%Y A049636 Cf. A007494.
%K A049636 nonn
%O A049636 0,1
%A A049636 _Clark Kimberling_
%E A049636 Terms a(38) onward added by _G. C. Greubel_, Dec 15 2017