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A191133 Increasing sequence generated by these rules: a(1)=1, and if x is in a then 3x+1 and 4x-2 are in a.

%I A191133 #8 Jul 13 2013 12:04:10
%S A191133 1,2,4,6,7,13,14,19,22,26,40,43,50,54,58,67,74,79,86,102,121,130,151,
%T A191133 158,163,170,175,198,202,214,223,230,238,259,266,294,307,314,342,364,
%U A191133 391,406,454,475,482,490,511,518,526,595,602,607,630,643,650,670,678,691,698,715,778,790,799,806,854,883,890,918,922,943,950
%N A191133 Increasing sequence generated by these rules:  a(1)=1, and if x is in a then 3x+1 and 4x-2 are in a.
%C A191133 See A191113.
%H A191133 Reinhard Zumkeller, <a href="/A191133/b191133.txt">Table of n, a(n) for n = 1..10000</a>
%t A191133 h = 3; i = 1; j = 4; k = -2; f = 1; g = 9;
%t A191133 a = Union[Flatten[NestList[{h # + i, j # + k} &, f, g]]]   (* A191133 *)
%t A191133 b = (a - 1)/3; c = (a + 2)/4; r = Range[1, 1500];
%t A191133 d = Intersection[b, r] (* A191190 *)
%t A191133 e = Intersection[c, r] (* A191191 *)
%o A191133 (Haskell)
%o A191133 import Data.Set (singleton, deleteFindMin, insert)
%o A191133 a191133 n = a191133_list !! (n-1)
%o A191133 a191133_list = f $ singleton 1
%o A191133    where f s = m : (f $ insert (3*m+1) $ insert (4*m-2) s')
%o A191133              where (m, s') = deleteFindMin s
%o A191133 -- _Reinhard Zumkeller_, Jun 01 2011
%Y A191133 Cf. A191113.
%K A191133 nonn
%O A191133 1,2
%A A191133 _Clark Kimberling_, May 27 2011