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A191115 Increasing sequence generated by these rules:  a(1)=1, and if x is in a then 3x-2 and 4x are in a. 3
1, 4, 10, 16, 28, 40, 46, 64, 82, 112, 118, 136, 160, 184, 190, 244, 256, 328, 334, 352, 406, 448, 472, 478, 544, 550, 568, 640, 730, 736, 760, 766, 976, 982, 1000, 1024, 1054, 1216, 1312, 1336, 1342, 1408, 1414, 1432, 1624, 1630, 1648, 1702, 1792, 1888, 1912, 1918, 2176, 2188, 2200, 2206, 2272, 2278, 2296, 2560, 2920 (list; graph; refs; listen; history; text; internal format)
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 = 0; f = 1; g = 9;

a = Union[Flatten[NestList[{h # + i, j # + k} &, f, g]]]  (* A191115 *)

b = (a + 2)/3; c = a/4; r = Range[1, 1500];

d = Intersection[b, r] (* A191113 *)

e = Intersection[c, r] (* A191154 *)

m = a/2 (* divisibility property *)

PROG

(Haskell)

import Data.Set (singleton, deleteFindMin, insert)

a191115 n = a191115_list !! (n-1)

a191115_list = 1 : f (singleton 4)

   where f s = m : (f $ insert (3*m-2) $ insert (4*m) s')

             where (m, s') = deleteFindMin s

-- Reinhard Zumkeller, Jun 01 2011

CROSSREFS

Cf. A191113.

Sequence in context: A132227 A036063 A112984 * A073121 A167346 A027430

Adjacent sequences:  A191112 A191113 A191114 * A191116 A191117 A191118

KEYWORD

nonn

AUTHOR

Clark Kimberling, May 27 2011

STATUS

approved

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Last modified February 22 06:05 EST 2019. Contains 320389 sequences. (Running on oeis4.)