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A190809 Increasing sequence generated by these rules: a(1)=1, and if x is in a then 2x and 3x+2 are in a.

%I A190809 #11 Jul 13 2013 12:04:09
%S A190809 1,2,4,5,8,10,14,16,17,20,26,28,32,34,40,44,50,52,53,56,62,64,68,80,
%T A190809 86,88,98,100,104,106,112,122,124,128,134,136,152,158,160,161,170,172,
%U A190809 176,188,194,196,200,206,208,212,224,242,244,248,256,260,266,268,272,296
%N A190809 Increasing sequence generated by these rules:  a(1)=1, and if x is in a then 2x and 3x+2 are in a.
%C A190809 See A190803.
%H A190809 Reinhard Zumkeller, <a href="/A190809/b190809.txt">Table of n, a(n) for n = 1..10000</a>
%t A190809 h = 2; i = 0; j = 3; k = 2; f = 1; g = 9 ;
%t A190809 a = Union[Flatten[NestList[{h # + i, j # + k} &, f, g]]]  (* A190809 *)
%t A190809 b = a/2; c = (a - 2)/3; r = Range[1, 900];
%t A190809 d = Intersection[b, r] (* A190853 *)
%t A190809 e = Intersection[c, r] (* A190854 *)
%o A190809 (Haskell)
%o A190809 import Data.Set (singleton, deleteFindMin, insert)
%o A190809 a190809 n = a190809_list !! (n-1)
%o A190809 a190809_list = f $ singleton 1
%o A190809    where f s = m : (f $ insert (2*m) $ insert (3*m+2) s')
%o A190809              where (m, s') = deleteFindMin s
%o A190809 -- _Reinhard Zumkeller_, Jun 01 2011
%Y A190809 Cf. A190803, A190853, A190854.
%K A190809 nonn
%O A190809 1,2
%A A190809 _Clark Kimberling_, May 20 2011
%E A190809 a(51)=224 inserted by _Reinhard Zumkeller_, Jun 01 2011