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A191133 Increasing sequence generated by these rules:  a(1)=1, and if x is in a then 3x+1 and 4x-2 are in a. 4
1, 2, 4, 6, 7, 13, 14, 19, 22, 26, 40, 43, 50, 54, 58, 67, 74, 79, 86, 102, 121, 130, 151, 158, 163, 170, 175, 198, 202, 214, 223, 230, 238, 259, 266, 294, 307, 314, 342, 364, 391, 406, 454, 475, 482, 490, 511, 518, 526, 595, 602, 607, 630, 643, 650, 670, 678, 691, 698, 715, 778, 790, 799, 806, 854, 883, 890, 918, 922, 943, 950 (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 = 1; j = 4; k = -2; f = 1; g = 9;

a = Union[Flatten[NestList[{h # + i, j # + k} &, f, g]]]   (* A191133 *)

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

d = Intersection[b, r] (* A191190 *)

e = Intersection[c, r] (* A191191 *)

PROG

(Haskell)

import Data.Set (singleton, deleteFindMin, insert)

a191133 n = a191133_list !! (n-1)

a191133_list = f $ singleton 1

   where f s = m : (f $ insert (3*m+1) $ insert (4*m-2) s')

             where (m, s') = deleteFindMin s

-- Reinhard Zumkeller, Jun 01 2011

CROSSREFS

Cf. A191113.

Sequence in context: A272589 A191191 A191190 * A050053 A272634 A084591

Adjacent sequences:  A191130 A191131 A191132 * A191134 A191135 A191136

KEYWORD

nonn

AUTHOR

Clark Kimberling, May 27 2011

STATUS

approved

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Last modified November 12 05:52 EST 2019. Contains 329051 sequences. (Running on oeis4.)