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A191145 Increasing sequence S generated by these rules: a(1)=1, and if x is in S then both 3x+2 and 4x+3 are in S.

%I A191145 #9 Jul 13 2013 12:04:11
%S A191145 1,5,7,17,23,31,53,71,95,127,161,215,287,383,485,511,647,863,1151,
%T A191145 1457,1535,1943,2047,2591,3455,4373,4607,5831,6143,7775,8191,10367,
%U A191145 13121,13823,17495,18431,23327,24575,31103,32767,39365,41471,52487,55295,69983,73727,93311,98303,118097,124415,131071,157463,165887
%N A191145 Increasing sequence S generated by these rules:  a(1)=1, and if x is in S then both 3x+2 and 4x+3 are in S.
%C A191145 See A191113.
%H A191145 Reinhard Zumkeller, <a href="/A191145/b191145.txt">Table of n, a(n) for n = 1..10000</a>
%t A191145 h = 3; i = 2; j = 4; k = 3; f = 1; g = 11;
%t A191145 a = Union[Flatten[NestList[{h # + i, j # + k} &, f, g]]]  (* A191145 *)
%t A191145 b = (a - 2)/3; c = (a - 3)/4; r = Range[1, 16000];
%t A191145 d = Intersection[b, r] (* A191145 *)
%t A191145 e = Intersection[c, r] (* A191145 *)
%t A191145 m = (a + 1)/2  (* A025613 *)
%o A191145 (Haskell)
%o A191145 import Data.Set (singleton, deleteFindMin, insert)
%o A191145 a191145 n = a191145_list !! (n-1)
%o A191145 a191145_list = f $ singleton 1
%o A191145    where f s = m : (f $ insert (3*m+2) $ insert (4*m+3) s')
%o A191145              where (m, s') = deleteFindMin s
%o A191145 -- _Reinhard Zumkeller_, Jun 01 2011
%Y A191145 See A191113.
%K A191145 nonn
%O A191145 1,2
%A A191145 _Clark Kimberling_, May 28 2011