A049636 - OEIS

%I #16 Dec 16 2017 05:27:27

%S 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 39,41,42,44,45,47,48,50,51,53,54,56,57,59,60,62,63,65,66,68,69,71,72,

%U 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 Congruent to 0 or 2 mod 3, but not equal to 0 or 3.

%C a(n) = T(n, 2), array T as in A049627.

%H G. C. Greubel, <a href="/A049636/b049636.txt">Table of n, a(n) for n = 0..1000</a>

%F O.g.f.: -(x+2)(x^2-x-1)/((1-x)^2*(1+x)). - _R. J. Mathar_, Aug 13 2008

%t 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 (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 Cf. A007494.

%K nonn

%O 0,1

%A _Clark Kimberling_

%E Terms a(38) onward added by _G. C. Greubel_, Dec 15 2017