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A191137 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 A191137 #8 Jul 13 2013 12:04:10
%S A191137 1,4,6,13,18,19,26,40,54,55,58,74,78,79,106,121,162,163,166,175,218,
%T A191137 222,223,234,235,238,298,314,318,319,364,426,486,487,490,499,526,650,
%U A191137 654,655,666,667,670,702,703,706,715,874,890,894,895,938,942,943,954,955,958,1093,1194,1258,1274,1278,1279,1458,1459,1462,1471
%N A191137 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 A191137 See A191113.
%H A191137 Reinhard Zumkeller, <a href="/A191137/b191137.txt">Table of n, a(n) for n = 1..10000</a>
%t A191137 h = 3; i = 1; j = 4; k = 2; f = 1; g = 9;
%t A191137 a = Union[Flatten[NestList[{h # + i, j # + k} &, f, g]]]   (* A191137 *)
%t A191137 b = (a - 1)/3; c = (a - 2)/4; r = Range[1, 1500];
%t A191137 d = Intersection[b, r] (* A191198 *)
%t A191137 e = Intersection[c, r] (* A191199 *)
%o A191137 (Haskell)
%o A191137 import Data.Set (singleton, deleteFindMin, insert)
%o A191137 a191137 n = a191137_list !! (n-1)
%o A191137 a191137_list = f $ singleton 1
%o A191137    where f s = m : (f $ insert (3*m+1) $ insert (4*m+2) s')
%o A191137              where (m, s') = deleteFindMin s
%o A191137 -- _Reinhard Zumkeller_, Jun 01 2011
%Y A191137 Cf. A191113.
%K A191137 nonn
%O A191137 1,2
%A A191137 _Clark Kimberling_, May 28 2011