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A191142 Increasing sequence generated by these rules:  a(1)=1, and if x is in a then 3x+2 and 4x are in a. 4
1, 4, 5, 14, 16, 17, 20, 44, 50, 53, 56, 62, 64, 68, 80, 134, 152, 161, 170, 176, 188, 194, 200, 206, 212, 224, 242, 248, 256, 272, 320, 404, 458, 485, 512, 530, 536, 566, 584, 602, 608, 620, 638, 644, 674, 680, 704, 728, 746, 752, 770, 776, 800, 818, 824, 848, 896, 962, 968, 992, 1024, 1088, 1214, 1280, 1376, 1457, 1538, 1592 (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]]]  (* A191142 *)

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

d = Intersection[b, r] (* A191208 *)

e = Intersection[c, r] (* A191209 *)

PROG

(Haskell)

import Data.Set (singleton, deleteFindMin, insert)

a191142 n = a191142_list !! (n-1)

a191142_list = f $ singleton 1

   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: A008540 A290810 A000867 * A049770 A262903 A079362

Adjacent sequences:  A191139 A191140 A191141 * A191143 A191144 A191145

KEYWORD

nonn

AUTHOR

Clark Kimberling, May 28 2011

STATUS

approved

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Last modified November 12 21:10 EST 2018. Contains 317116 sequences. (Running on oeis4.)