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A190807 Increasing sequence generated by these rules:  a(1)=1, and if x is in a then 2x and 3x-1 are in a. 4
1, 2, 4, 5, 8, 10, 11, 14, 16, 20, 22, 23, 28, 29, 32, 40, 41, 44, 46, 47, 56, 58, 59, 64, 65, 68, 80, 82, 83, 86, 88, 92, 94, 95, 112, 116, 118, 119, 122, 128, 130, 131, 136, 137, 140, 160, 164, 166, 167, 172, 173, 176, 184, 188, 190, 191, 194, 203, 224, 232, 236, 238, 239, 244, 245, 248, 256, 257, 260, 262, 263, 272, 274, 275, 280 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

See A190803.

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

MATHEMATICA

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

a = Union[Flatten[NestList[{h # + i, j # + k} &, f, g]]]  (* A190807 *)

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

d = Intersection[b, r] (* A190849 *)

e = Intersection[c, r] (* A190850 *)

PROG

(Haskell)

import Data.Set (singleton, deleteFindMin, insert)

a190807 n = a190807_list !! (n-1)

a190807_list = f $ singleton 1

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

             where (m, s') = deleteFindMin s

-- Reinhard Zumkeller, Jun 01 2011

CROSSREFS

Cf. A190803, A190849, A190850.

Sequence in context: A284880 A047261 A286687 * A289058 A102798 A247886

Adjacent sequences:  A190804 A190805 A190806 * A190808 A190809 A190810

KEYWORD

nonn

AUTHOR

Clark Kimberling, May 20 2011

STATUS

approved

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Last modified September 16 18:26 EDT 2021. Contains 347473 sequences. (Running on oeis4.)