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A191124
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, 5, 6, 10, 14, 17, 22, 26, 29, 41, 42, 50, 58, 65, 70, 77, 86, 90, 106, 118, 122, 125, 149, 166, 170, 173, 194, 202, 209, 230, 234, 257, 262, 269, 282, 310, 317, 346, 353, 362, 365, 374, 426, 446, 474, 490, 497, 502, 509, 518, 581, 598, 605, 626, 666, 682, 689, 694, 701, 770, 778, 785, 806, 810, 838, 845, 922, 929, 938, 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]]] (* A191124 *)
b = (a + 1)/3; c = (a - 2)/4; r = Range[1, 1500];
d = Intersection[b, r] (* A191172 *)
e = Intersection[c, r] (* A191173 *)
PROG
(Haskell)
import Data.Set (singleton, deleteFindMin, insert)
a191124 n = a191124_list !! (n-1)
a191124_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: A368045 A191748 A102212 * A281379 A348565 A316946
KEYWORD
nonn
AUTHOR
Clark Kimberling, May 27 2011
STATUS
approved