A190806 Increasing sequence generated by these rules: a(1)=1, and if x is in a then 2x-1 and 3x+2 are in a.

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

Offset

1,2

Comments

See A190803.

Links

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

Mathematica

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 *)

Prog

(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
-- Reinhard Zumkeller, Jun 01 2011

Crossrefs

Cf. A190803, A190848.

Sequence in context: A374672 A175543 A200078 * A294774 A192746 A081295

Adjacent sequences: A190803 A190804 A190805 * A190807 A190808 A190809

Keyword

nonn

Author

Clark Kimberling, May 20 2011

Extensions

a(56)=897 inserted by Reinhard Zumkeller, Jun 01 2011

Status

approved