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A191145 Increasing sequence S generated by these rules:  a(1)=1, and if x is in S then both 3x+2 and 4x+3 are in S. 2
1, 5, 7, 17, 23, 31, 53, 71, 95, 127, 161, 215, 287, 383, 485, 511, 647, 863, 1151, 1457, 1535, 1943, 2047, 2591, 3455, 4373, 4607, 5831, 6143, 7775, 8191, 10367, 13121, 13823, 17495, 18431, 23327, 24575, 31103, 32767, 39365, 41471, 52487, 55295, 69983, 73727, 93311, 98303, 118097, 124415, 131071, 157463, 165887 (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 = 3; f = 1; g = 11;

a = Union[Flatten[NestList[{h # + i, j # + k} &, f, g]]]  (* A191145 *)

b = (a - 2)/3; c = (a - 3)/4; r = Range[1, 16000];

d = Intersection[b, r] (* A191145 *)

e = Intersection[c, r] (* A191145 *)

m = (a + 1)/2  (* A025613 *)

PROG

(Haskell)

import Data.Set (singleton, deleteFindMin, insert)

a191145 n = a191145_list !! (n-1)

a191145_list = f $ singleton 1

   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

See A191113.

Sequence in context: A044966 A283159 A283145 * A145354 A214345 A166109

Adjacent sequences:  A191142 A191143 A191144 * A191146 A191147 A191148

KEYWORD

nonn

AUTHOR

Clark Kimberling, May 28 2011

STATUS

approved

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Last modified July 26 22:49 EDT 2021. Contains 346300 sequences. (Running on oeis4.)