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A191120 Increasing sequence generated by these rules:  a(1)=1, and if x is in a then 3x-1 and 4x-2 are in a. 5

%I

%S 1,2,5,6,14,17,18,22,41,50,53,54,65,66,70,86,122,149,158,161,162,194,

%T 197,198,209,210,214,257,258,262,278,342,365,446,473,482,485,486,581,

%U 590,593,594,626,629,630,641,642,646,770,773,774,785,786,790,833,834,838,854,1025,1026,1030,1046,1094,1110,1337,1366,1418,1445

%N 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 See A191113.

%H Reinhard Zumkeller, <a href="/A191120/b191120.txt">Table of n, a(n) for n = 1..10000</a>

%t h = 3; i = -1; j = 4; k = -2; f = 1; g = 9;

%t a = Union[Flatten[NestList[{h # + i, j # + k} &, f, g]]] (* A191120 *)

%t b = (a + 1)/3; c = (a + 2)/4; r = Range[1, 1500];

%t d = Intersection[b, r] (* A191229 *)

%t e = Intersection[c, r] (* A191165 *)

%o (Haskell)

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

%o a191120 n = a191120_list !! (n-1)

%o a191120_list = f $ singleton 1

%o where f s = m : (f $ insert (3*m-1) $ insert (4*m-2) s')

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

%o -- _Reinhard Zumkeller_, Jun 01 2011

%Y Cf. A191113, A191229, A191165.

%K nonn

%O 1,2

%A _Clark Kimberling_, May 27 2011

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Last modified May 31 06:22 EDT 2020. Contains 334747 sequences. (Running on oeis4.)