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A190806
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Increasing sequence generated by these rules: a(1)=1, and if x is in a then 2x-1 and 3x+2 are in a.
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3
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1, 5, 9, 17, 29, 33, 53, 57, 65, 89, 101, 105, 113, 129, 161, 173, 177, 197, 201, 209, 225, 257, 269, 305, 317, 321, 341, 345, 353, 389, 393, 401, 417, 449, 485, 513, 521, 533, 537, 593, 605, 609, 629, 633, 641, 677, 681, 689, 705, 773, 777, 785, 801, 809, 833, 897, 917, 953, 965, 969
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OFFSET
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1,2
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COMMENTS
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LINKS
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MATHEMATICA
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h = 2; i = -1; j = 3; k = 2; f = 1; g = 12 ;
a = Union[Flatten[NestList[{h # + i, j # + k} &, f, g]]] (* A190806 *)
b = (a + 1)/2; c = (a - 2)/3; r = Range[1, 1200];
d = Intersection[b, r] (* A190804 conjectured *)
e = Intersection[c, r] (* A190848 *)
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PROG
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(Haskell)
import Data.Set (singleton, deleteFindMin, insert)
a190806 n = a190806_list !! (n-1)
a190806_list = 1 : f (singleton 5)
where f s = m : (f $ insert (2*m-1) $ insert (3*m+2) s')
where (m, s') = deleteFindMin s
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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