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A191127 Increasing sequence generated by these rules: a(1)=1, and if x is in a then 3x and 4x-2 are in a.

%I A191127 #11 Jul 20 2021 14:46:02
%S A191127 1,2,3,6,9,10,18,22,27,30,34,38,54,66,70,81,86,90,102,106,114,118,134,
%T A191127 150,162,198,210,214,243,258,262,270,278,306,318,322,342,354,358,402,
%U A191127 406,422,450,454,470,486,534,594,598,630,642,646,729,774,786,790,810,834,838,854,918,954,966,970,1026,1030,1046,1062,1074,1078
%N A191127 Increasing sequence generated by these rules:  a(1)=1, and if x is in a then 3x and 4x-2 are in a.
%C A191127 See A191113.
%H A191127 Reinhard Zumkeller, <a href="/A191127/b191127.txt">Table of n, a(n) for n = 1..10000</a>
%t A191127 h = 3; i = 0; j = 4; k = -2; f = 1; g = 9;
%t A191127 a = Union[Flatten[NestList[{h # + i, j # + k} &, f, g]]]  (* A191127 *)
%t A191127 b = a/3; c = (a + 2)/4; r = Range[1, 1500];
%t A191127 d = Intersection[b, r] (* A191178 *)
%t A191127 e = Intersection[c, r] (* A191179 *)
%t A191127 Nest[Flatten[{#,3#,4#-2}]&,1,7]//Union (* _Harvey P. Dale_, Jul 20 2021 *)
%o A191127 (Haskell)
%o A191127 import Data.Set (singleton, deleteFindMin, insert)
%o A191127 a191127 n = a191127_list !! (n-1)
%o A191127 a191127_list = f $ singleton 1
%o A191127    where f s = m : (f $ insert (3*m) $ insert (4*m-2) s')
%o A191127              where (m, s') = deleteFindMin s
%o A191127 -- _Reinhard Zumkeller_, Jun 01 2011
%Y A191127 Cf. A191119, A191178, A191179.
%K A191127 nonn
%O A191127 1,2
%A A191127 _Clark Kimberling_, May 27 2011