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A191123 Increasing sequence generated by these rules:  a(1)=1, and if x is in a then 3x-1 and 4x+1 are in a. 4
1, 2, 5, 9, 14, 21, 26, 37, 41, 57, 62, 77, 85, 105, 110, 122, 149, 165, 170, 185, 229, 230, 249, 254, 309, 314, 329, 341, 365, 421, 441, 446, 489, 494, 509, 554, 597, 661, 681, 686, 689, 741, 746, 761, 917, 921, 926, 941, 986, 997, 1017, 1022, 1094, 1237, 1257, 1262, 1317, 1322, 1337, 1365, 1461, 1466, 1481, 1526, 1661, 1685 (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 = 1; f = 1; g = 9;

a = Union[Flatten[NestList[{h # + i, j # + k} &, f, g]]]  (* A191123 *)

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

d = Intersection[b, r] (* A191170 *)

e = Intersection[c, r] (* A191171 *)

PROG

(Haskell)

import Data.Set (singleton, deleteFindMin, insert)

a191123 n = a191123_list !! (n-1)

a191123_list = f $ singleton 1

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

             where (m, s') = deleteFindMin s

-- Reinhard Zumkeller, Jun 01 2011

CROSSREFS

Cf. A191113.

Sequence in context: A024669 A006482 A191170 * A152888 A139423 A026053

Adjacent sequences:  A191120 A191121 A191122 * A191124 A191125 A191126

KEYWORD

nonn

AUTHOR

Clark Kimberling, May 27 2011

STATUS

approved

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Last modified June 1 12:52 EDT 2020. Contains 334762 sequences. (Running on oeis4.)