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A191133
Increasing sequence generated by these rules: a(1)=1, and if x is in a then 3x+1 and 4x-2 are in a.
4
1, 2, 4, 6, 7, 13, 14, 19, 22, 26, 40, 43, 50, 54, 58, 67, 74, 79, 86, 102, 121, 130, 151, 158, 163, 170, 175, 198, 202, 214, 223, 230, 238, 259, 266, 294, 307, 314, 342, 364, 391, 406, 454, 475, 482, 490, 511, 518, 526, 595, 602, 607, 630, 643, 650, 670, 678, 691, 698, 715, 778, 790, 799, 806, 854, 883, 890, 918, 922, 943, 950
OFFSET
1,2
COMMENTS
See A191113.
LINKS
MATHEMATICA
h = 3; i = 1; j = 4; k = -2; f = 1; g = 9;
a = Union[Flatten[NestList[{h # + i, j # + k} &, f, g]]] (* A191133 *)
b = (a - 1)/3; c = (a + 2)/4; r = Range[1, 1500];
d = Intersection[b, r] (* A191190 *)
e = Intersection[c, r] (* A191191 *)
PROG
(Haskell)
import Data.Set (singleton, deleteFindMin, insert)
a191133 n = a191133_list !! (n-1)
a191133_list = f $ singleton 1
where f s = m : (f $ insert (3*m+1) $ insert (4*m-2) s')
where (m, s') = deleteFindMin s
-- Reinhard Zumkeller, Jun 01 2011
CROSSREFS
Cf. A191113.
Sequence in context: A272589 A191191 A191190 * A050053 A272634 A084591
KEYWORD
nonn
AUTHOR
Clark Kimberling, May 27 2011
STATUS
approved