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A190809 Increasing sequence generated by these rules:  a(1)=1, and if x is in a then 2x and 3x+2 are in a. 4
1, 2, 4, 5, 8, 10, 14, 16, 17, 20, 26, 28, 32, 34, 40, 44, 50, 52, 53, 56, 62, 64, 68, 80, 86, 88, 98, 100, 104, 106, 112, 122, 124, 128, 134, 136, 152, 158, 160, 161, 170, 172, 176, 188, 194, 196, 200, 206, 208, 212, 224, 242, 244, 248, 256, 260, 266, 268, 272, 296 (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 = 2; f = 1; g = 9 ;

a = Union[Flatten[NestList[{h # + i, j # + k} &, f, g]]]  (* A190809 *)

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

d = Intersection[b, r] (* A190853 *)

e = Intersection[c, r] (* A190854 *)

PROG

(Haskell)

import Data.Set (singleton, deleteFindMin, insert)

a190809 n = a190809_list !! (n-1)

a190809_list = f $ singleton 1

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

             where (m, s') = deleteFindMin s

-- Reinhard Zumkeller, Jun 01 2011

CROSSREFS

Cf. A190803, A190853, A190854.

Sequence in context: A018498 A002048 A174989 * A067941 A259711 A182195

Adjacent sequences:  A190806 A190807 A190808 * A190810 A190811 A190812

KEYWORD

nonn

AUTHOR

Clark Kimberling, May 20 2011

EXTENSIONS

a(51)=224 inserted by Reinhard Zumkeller, Jun 01 2011

STATUS

approved

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Last modified August 8 23:02 EDT 2020. Contains 336300 sequences. (Running on oeis4.)