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A191126 Increasing sequence generated by these rules: a(1)=1, and if x is in a then 3x and 4x-3 are in a.

%I A191126 #9 Jul 13 2013 12:04:10
%S A191126 1,3,9,27,33,81,99,105,129,243,297,315,321,387,393,417,513,729,891,
%T A191126 945,963,969,1161,1179,1185,1251,1257,1281,1539,1545,1569,1665,2049,
%U A191126 2187,2673,2835,2889,2907,2913,3483,3537,3555,3561,3753,3771,3777,3843,3849,3873,4617,4635,4641,4707,4713,4737,4995,5001,5025,5121
%N A191126 Increasing sequence generated by these rules:  a(1)=1, and if x is in a then 3x and 4x-3 are in a.
%C A191126 See A191113.
%H A191126 Reinhard Zumkeller, <a href="/A191126/b191126.txt">Table of n, a(n) for n = 1..10000</a>
%t A191126 h = 3; i = 0; j = 4; k = -3; f = 1; g = 9;
%t A191126 a = Union[Flatten[NestList[{h # + i, j # + k} &, f, g]]]  (* A191126 *)
%t A191126 b = a/3; c = (a + 3)/4; r = Range[1, 1500];
%t A191126 d = Intersection[b, r] (* A191176 *)
%t A191126 e = Intersection[c, r] (* A191177 *)
%t A191126 m = a/3   (* divisibility property *)
%t A191126 p = (a + 3)/6  (* divisibility property *)
%o A191126 (Haskell)
%o A191126 import Data.Set (singleton, deleteFindMin, insert)
%o A191126 a191126 n = a191126_list !! (n-1)
%o A191126 a191126_list = 1 : f (singleton 3)
%o A191126    where f s = m : (f $ insert (3*m) $ insert (4*m-3) s')
%o A191126              where (m, s') = deleteFindMin s
%o A191126 -- _Reinhard Zumkeller_, Jun 01 2011
%Y A191126 Cf. A191113.
%K A191126 nonn
%O A191126 1,2
%A A191126 _Clark Kimberling_, May 27 2011