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A191142 Increasing sequence generated by these rules:  a(1)=1, and if x is in a then 3x+2 and 4x are in a. 4

%I

%S 1,4,5,14,16,17,20,44,50,53,56,62,64,68,80,134,152,161,170,176,188,

%T 194,200,206,212,224,242,248,256,272,320,404,458,485,512,530,536,566,

%U 584,602,608,620,638,644,674,680,704,728,746,752,770,776,800,818,824,848,896,962,968,992,1024,1088,1214,1280,1376,1457,1538,1592

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

%C See A191113.

%H Reinhard Zumkeller, <a href="/A191142/b191142.txt">Table of n, a(n) for n = 1..10000</a>

%t h = 3; i = 2; j = 4; k = 0; f = 1; g = 9;

%t a = Union[Flatten[NestList[{h # + i, j # + k} &, f, g]]] (* A191142 *)

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

%t d = Intersection[b, r] (* A191208 *)

%t e = Intersection[c, r] (* A191209 *)

%o (Haskell)

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

%o a191142 n = a191142_list !! (n-1)

%o a191142_list = f $ singleton 1

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

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

%o -- _Reinhard Zumkeller_, Jun 01 2011

%Y Cf. A191113.

%K nonn

%O 1,2

%A _Clark Kimberling_, May 28 2011

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Last modified August 2 12:30 EDT 2021. Contains 346424 sequences. (Running on oeis4.)