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

%I #11 Jul 13 2013 12:04:09

%S 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 86,88,98,100,104,106,112,122,124,128,134,136,152,158,160,161,170,172,

%U 176,188,194,196,200,206,208,212,224,242,244,248,256,260,266,268,272,296

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

%C See A190803.

%H Reinhard Zumkeller, <a href="/A190809/b190809.txt">Table of n, a(n) for n = 1..10000</a>

%t h = 2; i = 0; j = 3; k = 2; f = 1; g = 9 ;

%t a = Union[Flatten[NestList[{h # + i, j # + k} &, f, g]]] (* A190809 *)

%t b = a/2; c = (a - 2)/3; r = Range[1, 900];

%t d = Intersection[b, r] (* A190853 *)

%t e = Intersection[c, r] (* A190854 *)

%o (Haskell)

%o import Data.Set (singleton, deleteFindMin, insert)

%o a190809 n = a190809_list !! (n-1)

%o a190809_list = f $ singleton 1

%o where f s = m : (f $ insert (2*m) $ insert (3*m+2) s')

%o where (m, s') = deleteFindMin s

%o -- _Reinhard Zumkeller_, Jun 01 2011

%Y Cf. A190803, A190853, A190854.

%K nonn

%O 1,2

%A _Clark Kimberling_, May 20 2011

%E a(51)=224 inserted by _Reinhard Zumkeller_, Jun 01 2011