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A191144
Increasing sequence generated by these rules: a(1)=1, and if x is in a then 3x+2 and 4x+2 are in a.
4
1, 5, 6, 17, 20, 22, 26, 53, 62, 68, 70, 80, 82, 90, 106, 161, 188, 206, 212, 214, 242, 248, 250, 272, 274, 282, 320, 322, 330, 362, 426, 485, 566, 620, 638, 644, 646, 728, 746, 752, 754, 818, 824, 826, 848, 850, 858, 962, 968, 970, 992, 994, 1002, 1088, 1090, 1098, 1130, 1280, 1282, 1290, 1322, 1450, 1457, 1700, 1706, 1862
OFFSET
1,2
COMMENTS
See A191113.
LINKS
MATHEMATICA
h = 3; i = 2; j = 4; k = 2; f = 1; g = 9;
a = Union[Flatten[NestList[{h # + i, j # + k} &, f, g]]] (* A191144 *)
b = (a - 2)/3; c = (a - 2)/4; r = Range[1, 1500];
d = Intersection[b, r] (* A191212 *)
e = Intersection[c, r] (* A191213 *)
PROG
(Haskell)
import Data.Set (singleton, deleteFindMin, insert)
a191144 n = a191144_list !! (n-1)
a191144_list = f $ singleton 1
where f s = m : (f $ insert (3*m+2) $ insert (4*m+2) s')
where (m, s') = deleteFindMin s
-- Reinhard Zumkeller, Jun 01 2011
CROSSREFS
Cf. A191113.
Sequence in context: A059013 A355321 A327102 * A327097 A035595 A099571
KEYWORD
nonn
AUTHOR
Clark Kimberling, May 28 2011
STATUS
approved