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A191115 Increasing sequence generated by these rules: a(1)=1, and if x is in a then 3x-2 and 4x are in a.

%I A191115 #10 Jul 13 2013 12:04:09
%S A191115 1,4,10,16,28,40,46,64,82,112,118,136,160,184,190,244,256,328,334,352,
%T A191115 406,448,472,478,544,550,568,640,730,736,760,766,976,982,1000,1024,
%U A191115 1054,1216,1312,1336,1342,1408,1414,1432,1624,1630,1648,1702,1792,1888,1912,1918,2176,2188,2200,2206,2272,2278,2296,2560,2920
%N A191115 Increasing sequence generated by these rules:  a(1)=1, and if x is in a then 3x-2 and 4x are in a.
%C A191115 See A191113.
%H A191115 Reinhard Zumkeller, <a href="/A191115/b191115.txt">Table of n, a(n) for n = 1..10000</a>
%t A191115 h = 3; i = -2; j = 4; k = 0; f = 1; g = 9;
%t A191115 a = Union[Flatten[NestList[{h # + i, j # + k} &, f, g]]]  (* A191115 *)
%t A191115 b = (a + 2)/3; c = a/4; r = Range[1, 1500];
%t A191115 d = Intersection[b, r] (* A191113 *)
%t A191115 e = Intersection[c, r] (* A191154 *)
%t A191115 m = a/2 (* divisibility property *)
%o A191115 (Haskell)
%o A191115 import Data.Set (singleton, deleteFindMin, insert)
%o A191115 a191115 n = a191115_list !! (n-1)
%o A191115 a191115_list = 1 : f (singleton 4)
%o A191115    where f s = m : (f $ insert (3*m-2) $ insert (4*m) s')
%o A191115              where (m, s') = deleteFindMin s
%o A191115 -- _Reinhard Zumkeller_, Jun 01 2011
%Y A191115 Cf. A191113.
%K A191115 nonn
%O A191115 1,2
%A A191115 _Clark Kimberling_, May 27 2011