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A190807 Increasing sequence generated by these rules: a(1)=1, and if x is in a then 2x and 3x-1 are in a.

%I A190807 #9 Jul 13 2013 12:04:09
%S A190807 1,2,4,5,8,10,11,14,16,20,22,23,28,29,32,40,41,44,46,47,56,58,59,64,
%T A190807 65,68,80,82,83,86,88,92,94,95,112,116,118,119,122,128,130,131,136,
%U A190807 137,140,160,164,166,167,172,173,176,184,188,190,191,194,203,224,232,236,238,239,244,245,248,256,257,260,262,263,272,274,275,280
%N A190807 Increasing sequence generated by these rules:  a(1)=1, and if x is in a then 2x and 3x-1 are in a.
%C A190807 See A190803.
%H A190807 Reinhard Zumkeller, <a href="/A190807/b190807.txt">Table of n, a(n) for n = 1..10000</a>
%t A190807 h = 2; i = 0; j = 3; k = -1; f = 1; g = 9 ;
%t A190807 a = Union[Flatten[NestList[{h # + i, j # + k} &, f, g]]]  (* A190807 *)
%t A190807 b = a/2; c = (a + 1)/3; r = Range[1, 900];
%t A190807 d = Intersection[b, r] (* A190849 *)
%t A190807 e = Intersection[c, r] (* A190850 *)
%o A190807 (Haskell)
%o A190807 import Data.Set (singleton, deleteFindMin, insert)
%o A190807 a190807 n = a190807_list !! (n-1)
%o A190807 a190807_list = f $ singleton 1
%o A190807    where f s = m : (f $ insert (2*m) $ insert (3*m-1) s')
%o A190807              where (m, s') = deleteFindMin s
%o A190807 -- _Reinhard Zumkeller_, Jun 01 2011
%Y A190807 Cf. A190803, A190849, A190850.
%K A190807 nonn
%O A190807 1,2
%A A190807 _Clark Kimberling_, May 20 2011