login
A191116
Increasing sequence generated by these rules: a(1)=1, and if x is in a then 3x-2 and 4x+1 are in a.
3
1, 5, 13, 21, 37, 53, 61, 85, 109, 149, 157, 181, 213, 245, 253, 325, 341, 437, 445, 469, 541, 597, 629, 637, 725, 733, 757, 853, 973, 981, 1013, 1021, 1301, 1309, 1333, 1365, 1405, 1621, 1749, 1781, 1789, 1877, 1885, 1909, 2165, 2173, 2197, 2269, 2389, 2517, 2549, 2557, 2901, 2917, 2933, 2941, 3029, 3037, 3061, 3413
OFFSET
1,2
COMMENTS
See A191113.
LINKS
MATHEMATICA
h = 3; i = -2; j = 4; k = 1; f = 1; g = 9;
a = Union[Flatten[NestList[{h # + i, j # + k} &, f, g]]] (* A191116 *)
b = (a + 2)/3; c = (a - 1)/4; r = Range[1, 1500];
d = Intersection[b, r] (* A191155 *)
e = Intersection[c, r] (* A191129 *)
m = (a + 1)/2 (* divisibility property *)
p = (a + 3)/4 (* divisibility property *)
q = (a + 3)/8 (* divisibility property *)
PROG
(Haskell)
import Data.Set (singleton, deleteFindMin, insert)
a191116 n = a191116_list !! (n-1)
a191116_list = 1 : f (singleton 5)
where f s = m : (f $ insert (3*m-2) $ insert (4*m+1) s')
where (m, s') = deleteFindMin s
-- Reinhard Zumkeller, Jun 01 2011
CROSSREFS
Cf. A191113.
Sequence in context: A252296 A273569 A273750 * A166051 A160170 A277189
KEYWORD
nonn
AUTHOR
Clark Kimberling, May 27 2011
STATUS
approved