A191118 Increasing sequence generated by these rules: a(1)=1, and if x is in a then 3x-2 and 4x+3 are in a.

1, 7, 19, 31, 55, 79, 91, 127, 163, 223, 235, 271, 319, 367, 379, 487, 511, 655, 667, 703, 811, 895, 943, 955, 1087, 1099, 1135, 1279, 1459, 1471, 1519, 1531, 1951, 1963, 1999, 2047, 2107, 2431, 2623, 2671, 2683, 2815, 2827, 2863, 3247, 3259, 3295, 3403, 3583, 3775, 3823, 3835, 4351, 4375, 4399, 4411, 4543, 4555, 4591

Offset

1,2

Comments

See A191113.

Links

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

Mathematica

h = 3; i = -2; j = 4; k = 3; f = 1; g = 9;
a = Union[Flatten[NestList[{h # + i, j # + k} &, f, g]]]  (* A191118 *)
b = (a + 2)/3; c = (a - 3)/4; r = Range[1, 1500];
d = Intersection[b, r] (* A191114 *)
e = Intersection[c, r] (* A191138 *)

Prog

(Haskell)
import Data.Set (singleton, deleteFindMin, insert)
a191118 n = a191118_list !! (n-1)
a191118_list = 1 : f (singleton 7)
   where f s = m : (f $ insert (3*m-2) $ insert (4*m+3) s')
             where (m, s') = deleteFindMin s
-- Reinhard Zumkeller, Jun 01 2011

Crossrefs

Cf. A191113.

Sequence in context: A071696 A216530 A114564 * A298019 A169605 A216532

Adjacent sequences: A191115 A191116 A191117 * A191119 A191120 A191121

Keyword

nonn

Author

Clark Kimberling, May 27 2011

Status

approved