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%I #10 Jul 13 2013 12:04:09
%S 1,2,4,7,8,13,14,16,22,25,26,28,32,40,43,44,49,50,52,56,64,67,76,79,
%T 80,85,86,88,97,98,100,104,112,121,128,130,133,134,148,151,152,157,
%U 158,160,169,170,172,176,193,194,196,200,202,208,224,229,238,241,242,256
%N Increasing sequence generated by these rules: a(1)=1, and if x is in a then 2x and 3x+1 are in a.
%C See A190803.
%H Reinhard Zumkeller, <a href="/A190808/b190808.txt">Table of n, a(n) for n = 1..10000</a>
%t h = 2; i = 0; j = 3; k = 1; f = 1; g = 9 ;
%t a = Union[Flatten[NestList[{h # + i, j # + k} &, f, g]]] (* A190808 *)
%t b = a/2; c = (a - 1)/3; r = Range[1, 900];
%t d = Intersection[b, r] (* A190851 *)
%t e = Intersection[c, r] (* A190852 *)
%o (Haskell)
%o import Data.Set (singleton, deleteFindMin, insert)
%o a190808 n = a190808_list !! (n-1)
%o a190808_list = f $ singleton 1
%o where f s = m : (f $ insert (2*m) $ insert (3*m+1) s')
%o where (m, s') = deleteFindMin s
%o -- _Reinhard Zumkeller_, Jun 01 2011
%Y Cf. A190803, A190851, A190852.
%K nonn
%O 1,2
%A _Clark Kimberling_, May 20 2011
%E a(55)=224 inserted by _Reinhard Zumkeller_, Jun 01 2011
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