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A191135 Increasing sequence generated by these rules: a(1)=1, and if x is in a then 3x+1 and 4x are in a.

%I A191135 #8 Jul 13 2013 12:04:10
%S A191135 1,4,13,16,40,49,52,64,121,148,157,160,193,196,208,256,364,445,472,
%T A191135 481,484,580,589,592,625,628,640,769,772,784,832,1024,1093,1336,1417,
%U A191135 1444,1453,1456,1741,1768,1777,1780,1876,1885,1888,1921,1924,1936,2308,2317,2320,2353,2356,2368,2497,2500,2512,2560,3073,3076
%N A191135 Increasing sequence generated by these rules:  a(1)=1, and if x is in a then 3x+1 and 4x are in a.
%C A191135 See A191113.
%H A191135 Reinhard Zumkeller, <a href="/A191135/b191135.txt">Table of n, a(n) for n = 1..10000</a>
%t A191135 h = 3; i = 1; j = 4; k = 0; f = 1; g = 9;
%t A191135 a = Union[Flatten[NestList[{h # + i, j # + k} &, f, g]]]   (* A191135 *)
%t A191135 b = (a - 1)/3; c = a/4; r = Range[1, 1500];
%t A191135 d = Intersection[b, r] (* A191136 *)
%t A191135 e = Intersection[c, r] (* A191195 *)
%o A191135 (Haskell)
%o A191135 import Data.Set (singleton, deleteFindMin, insert)
%o A191135 a191135 n = a191135_list !! (n-1)
%o A191135 a191135_list = f $ singleton 1
%o A191135    where f s = m : (f $ insert (3*m+1) $ insert (4*m) s')
%o A191135              where (m, s') = deleteFindMin s
%o A191135 -- _Reinhard Zumkeller_, Jun 01 2011
%Y A191135 Cf. A191113.
%K A191135 nonn
%O A191135 1,2
%A A191135 _Clark Kimberling_, May 28 2011