A191135 Increasing sequence generated by these rules: a(1)=1, and if x is in a then 3x+1 and 4x are in a.

1, 4, 13, 16, 40, 49, 52, 64, 121, 148, 157, 160, 193, 196, 208, 256, 364, 445, 472, 481, 484, 580, 589, 592, 625, 628, 640, 769, 772, 784, 832, 1024, 1093, 1336, 1417, 1444, 1453, 1456, 1741, 1768, 1777, 1780, 1876, 1885, 1888, 1921, 1924, 1936, 2308, 2317, 2320, 2353, 2356, 2368, 2497, 2500, 2512, 2560, 3073, 3076

Offset

1,2

Comments

See A191113.

Links

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

Mathematica

h = 3; i = 1; j = 4; k = 0; f = 1; g = 9;
a = Union[Flatten[NestList[{h # + i, j # + k} &, f, g]]]   (* A191135 *)
b = (a - 1)/3; c = a/4; r = Range[1, 1500];
d = Intersection[b, r] (* A191136 *)
e = Intersection[c, r] (* A191195 *)

Prog

(Haskell)
import Data.Set (singleton, deleteFindMin, insert)
a191135 n = a191135_list !! (n-1)
a191135_list = f $ singleton 1
   where f s = m : (f $ insert (3*m+1) $ insert (4*m) s')
             where (m, s') = deleteFindMin s
-- Reinhard Zumkeller, Jun 01 2011

Crossrefs

Cf. A191113.

Sequence in context: A031208 A228137 A301965 * A268524 A032824 A367326

Adjacent sequences: A191132 A191133 A191134 * A191136 A191137 A191138

Keyword

nonn

Author

Clark Kimberling, May 28 2011

Status

approved