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A191130 Increasing sequence generated by these rules: a(1)=1, and if x is in a then 3x and 4x+2 are in a.

%I A191130 #8 Jul 13 2013 12:04:10
%S A191130 1,3,6,9,14,18,26,27,38,42,54,58,74,78,81,106,110,114,126,154,162,170,
%T A191130 174,218,222,234,243,298,314,318,326,330,342,378,426,442,458,462,486,
%U A191130 506,510,522,618,650,654,666,682,698,702,729,874,890,894,938,942,954,974,978,990,1026,1134,1194,1258,1274,1278,1306,1322,1326
%N A191130 Increasing sequence generated by these rules:  a(1)=1, and if x is in a then 3x and 4x+2 are in a.
%C A191130 See A191113.
%H A191130 Reinhard Zumkeller, <a href="/A191130/b191130.txt">Table of n, a(n) for n = 1..10000</a>
%t A191130 h = 3; i = 0; j = 4; k = 2; f = 1; g = 9;
%t A191130 a = Union[Flatten[NestList[{h # + i, j # + k} &, f, g]]]  (* A191130 *)
%t A191130 b = a/3; c = (a - 2)/4; r = Range[1, 1500];
%t A191130 d = Intersection[b, r] (* A191184 *)
%t A191130 e = Intersection[c, r] (* A191185 *)
%o A191130 (Haskell)
%o A191130 import Data.Set (singleton, deleteFindMin, insert)
%o A191130 a191130 n = a191130_list !! (n-1)
%o A191130 a191130_list = f $ singleton 1
%o A191130    where f s = m : (f $ insert (3*m) $ insert (4*m+2) s')
%o A191130              where (m, s') = deleteFindMin s
%o A191130 -- _Reinhard Zumkeller_, Jun 01 2011
%Y A191130 Cf. A191113.
%K A191130 nonn
%O A191130 1,2
%A A191130 _Clark Kimberling_, May 27 2011