A190809 Increasing sequence generated by these rules: a(1)=1, and if x is in a then 2x and 3x+2 are in a.

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

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