login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

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