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A191142 Increasing sequence generated by these rules: a(1)=1, and if x is in a then 3x+2 and 4x are in a.

%I A191142 #8 Jul 13 2013 12:04:10
%S A191142 1,4,5,14,16,17,20,44,50,53,56,62,64,68,80,134,152,161,170,176,188,
%T A191142 194,200,206,212,224,242,248,256,272,320,404,458,485,512,530,536,566,
%U A191142 584,602,608,620,638,644,674,680,704,728,746,752,770,776,800,818,824,848,896,962,968,992,1024,1088,1214,1280,1376,1457,1538,1592
%N A191142 Increasing sequence generated by these rules:  a(1)=1, and if x is in a then 3x+2 and 4x are in a.
%C A191142 See A191113.
%H A191142 Reinhard Zumkeller, <a href="/A191142/b191142.txt">Table of n, a(n) for n = 1..10000</a>
%t A191142 h = 3; i = 2; j = 4; k = 0; f = 1; g = 9;
%t A191142 a = Union[Flatten[NestList[{h # + i, j # + k} &, f, g]]]  (* A191142 *)
%t A191142 b = (a - 2)/3; c = a/4; r = Range[1, 1500];
%t A191142 d = Intersection[b, r] (* A191208 *)
%t A191142 e = Intersection[c, r] (* A191209 *)
%o A191142 (Haskell)
%o A191142 import Data.Set (singleton, deleteFindMin, insert)
%o A191142 a191142 n = a191142_list !! (n-1)
%o A191142 a191142_list = f $ singleton 1
%o A191142    where f s = m : (f $ insert (3*m+2) $ insert (4*m) s')
%o A191142              where (m, s') = deleteFindMin s
%o A191142 -- _Reinhard Zumkeller_, Jun 01 2011
%Y A191142 Cf. A191113.
%K A191142 nonn
%O A191142 1,2
%A A191142 _Clark Kimberling_, May 28 2011