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 A190805 Increasing sequence generated by these rules:  a(1)=1, and if x is in a then 2x-1 and 3x+1 are in a. 3
 1, 4, 7, 13, 22, 25, 40, 43, 49, 67, 76, 79, 85, 97, 121, 130, 133, 148, 151, 157, 169, 193, 202, 229, 238, 241, 256, 259, 265, 292, 295, 301, 313, 337, 364, 385, 391, 400, 403, 445, 454, 457, 472, 475, 481, 508, 511, 517, 529, 580, 583, 589, 601, 607, 625, 673, 688, 715, 724, 727 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS See A190803. LINKS Reinhard Zumkeller, Table of n, a(n) for n = 1..10000 MATHEMATICA h = 2; i = -1; j = 3; k = 1; f = 1; g = 10 ; a = Union[Flatten[NestList[{h # + i, j # + k} &, f, g]]]  (* A190805 *) b = (a + 1)/2; c = (a - 1)/3; r = Range[1, 500]; d = Intersection[b, r] (* A190845 *) e = Intersection[c, r] (* A190808 conjectured *) PROG (Haskell) import Data.Set (singleton, deleteFindMin, insert) a190805 n = a190805_list !! (n-1) a190805_list = 1 : f (singleton 4)    where f s = m : (f \$ insert (2*m-1) \$ insert (3*m+1) s')              where (m, s') = deleteFindMin s -- Reinhard Zumkeller, Jun 01 2011 CROSSREFS Cf. A190803, A190845. Sequence in context: A068940 A147487 A190845 * A008471 A156622 A111314 Adjacent sequences:  A190802 A190803 A190804 * A190806 A190807 A190808 KEYWORD nonn AUTHOR Clark Kimberling, May 20 2011 EXTENSIONS a(56)=673 inserted by Reinhard Zumkeller, Jun 01 2011 STATUS approved

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Last modified December 2 08:31 EST 2021. Contains 349437 sequences. (Running on oeis4.)