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A191135
Increasing sequence generated by these rules: a(1)=1, and if x is in a then 3x+1 and 4x are in a.
3
1, 4, 13, 16, 40, 49, 52, 64, 121, 148, 157, 160, 193, 196, 208, 256, 364, 445, 472, 481, 484, 580, 589, 592, 625, 628, 640, 769, 772, 784, 832, 1024, 1093, 1336, 1417, 1444, 1453, 1456, 1741, 1768, 1777, 1780, 1876, 1885, 1888, 1921, 1924, 1936, 2308, 2317, 2320, 2353, 2356, 2368, 2497, 2500, 2512, 2560, 3073, 3076
OFFSET
1,2
COMMENTS
See A191113.
LINKS
MATHEMATICA
h = 3; i = 1; j = 4; k = 0; f = 1; g = 9;
a = Union[Flatten[NestList[{h # + i, j # + k} &, f, g]]] (* A191135 *)
b = (a - 1)/3; c = a/4; r = Range[1, 1500];
d = Intersection[b, r] (* A191136 *)
e = Intersection[c, r] (* A191195 *)
PROG
(Haskell)
import Data.Set (singleton, deleteFindMin, insert)
a191135 n = a191135_list !! (n-1)
a191135_list = f $ singleton 1
where f s = m : (f $ insert (3*m+1) $ insert (4*m) s')
where (m, s') = deleteFindMin s
-- Reinhard Zumkeller, Jun 01 2011
CROSSREFS
Cf. A191113.
Sequence in context: A031208 A228137 A301965 * A268524 A032824 A367326
KEYWORD
nonn
AUTHOR
Clark Kimberling, May 28 2011
STATUS
approved