login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A191118 Increasing sequence generated by these rules:  a(1)=1, and if x is in a then 3x-2 and 4x+3 are in a. 2
1, 7, 19, 31, 55, 79, 91, 127, 163, 223, 235, 271, 319, 367, 379, 487, 511, 655, 667, 703, 811, 895, 943, 955, 1087, 1099, 1135, 1279, 1459, 1471, 1519, 1531, 1951, 1963, 1999, 2047, 2107, 2431, 2623, 2671, 2683, 2815, 2827, 2863, 3247, 3259, 3295, 3403, 3583, 3775, 3823, 3835, 4351, 4375, 4399, 4411, 4543, 4555, 4591 (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 = 9;

a = Union[Flatten[NestList[{h # + i, j # + k} &, f, g]]]  (* A191118 *)

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

d = Intersection[b, r] (* A191114 *)

e = Intersection[c, r] (* A191138 *)

PROG

(Haskell)

import Data.Set (singleton, deleteFindMin, insert)

a191118 n = a191118_list !! (n-1)

a191118_list = 1 : f (singleton 7)

   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

Cf. A191113.

Sequence in context: A071696 A216530 A114564 * A298019 A169605 A216532

Adjacent sequences:  A191115 A191116 A191117 * A191119 A191120 A191121

KEYWORD

nonn

AUTHOR

Clark Kimberling, May 27 2011

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified May 30 23:34 EDT 2020. Contains 334747 sequences. (Running on oeis4.)