A191134 Increasing sequence generated by these rules: a(1)=1, and if x is in a then 3x+1 and 4x-1 are in a.

1, 3, 4, 10, 11, 13, 15, 31, 34, 39, 40, 43, 46, 51, 59, 94, 103, 118, 121, 123, 130, 135, 139, 154, 155, 159, 171, 178, 183, 203, 235, 283, 310, 355, 364, 370, 375, 391, 406, 411, 418, 463, 466, 471, 478, 483, 491, 514, 519, 535, 539, 550, 555, 610, 615, 619, 635, 683, 706, 711, 731, 811, 850, 931, 939, 1066, 1093, 1111, 1126

Offset

1,2

Comments

See A101113/

Links

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

Mathematica

h = 3; i = 1; j = 4; k = -1; f = 1; g = 9;
a = Union[Flatten[NestList[{h # + i, j # + k} &, f, g]]]   (* A191134 *)
b = (a - 1)/3; c = (a + 1)/4; r = Range[1, 1500];
d = Intersection[b, r] (* A191192 *)
e = Intersection[c, r] (* A191193 *)

Prog

(Haskell)
import Data.Set (singleton, deleteFindMin, insert)
a191134 n = a191134_list !! (n-1)
a191134_list = f $ singleton 1
   where f s = m : (f $ insert (3*m+1) $ insert (4*m-1) s')
             where (m, s') = deleteFindMin s
-- Reinhard Zumkeller, Jun 01 2011

Crossrefs

Cf. A191113.

Sequence in context: A139063 A224853 A225571 * A196101 A200816 A327300

Adjacent sequences: A191131 A191132 A191133 * A191135 A191136 A191137

Keyword

nonn

Author

Clark Kimberling, May 28 2011

Status

approved