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A191117
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, 6, 16, 26, 46, 66, 76, 106, 136, 186, 196, 226, 266, 306, 316, 406, 426, 546, 556, 586, 676, 746, 786, 796, 906, 916, 946, 1066, 1216, 1226, 1266, 1276, 1626, 1636, 1666, 1706, 1756, 2026, 2186, 2226, 2236, 2346, 2356, 2386, 2706, 2716, 2746, 2836, 2986, 3146, 3186, 3196, 3626, 3646, 3666, 3676, 3786, 3796, 3826
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]]] (* A191117 *)
b = (a + 2)/3; c = (a - 2)/4; r = Range[1, 1500];
d = Intersection[b, r] (* A191157 *)
e = Intersection[c, r] (* A191158 *)
m = (a + 4)/10 (* divisibility property *)
PROG
(Haskell)
import Data.Set (singleton, deleteFindMin, insert)
a191117 n = a191117_list !! (n-1)
a191117_list = 1 : f (singleton 6)
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: A341400 A367295 A212905 * A265389 A320693 A274848
KEYWORD
nonn
AUTHOR
Clark Kimberling, May 27 2011
STATUS
approved