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A191141 Increasing sequence generated by these rules: a(1)=1, and if x is in a then 3x+2 and 4x-1 are in a.

%I A191141 #8 Jul 13 2013 12:04:10
%S A191141 1,3,5,11,17,19,35,43,53,59,67,75,107,131,139,161,171,179,203,211,227,
%T A191141 235,267,299,323,395,419,427,485,515,523,539,555,611,635,643,683,707,
%U A191141 715,803,811,843,899,907,939,971,1067,1187,1195,1259,1283,1291,1457,1547,1571,1579,1619,1667,1675,1707,1835,1907,1931,1939,2051
%N A191141 Increasing sequence generated by these rules:  a(1)=1, and if x is in a then 3x+2 and 4x-1 are in a.
%C A191141 See A191113.
%H A191141 Reinhard Zumkeller, <a href="/A191141/b191141.txt">Table of n, a(n) for n = 1..10000</a>
%t A191141 h = 3; i = 2; j = 4; k = -1; f = 1; g = 9;
%t A191141 a = Union[Flatten[NestList[{h # + i, j # + k} &, f, g]]]  (* A191141 *)
%t A191141 b = (a - 2)/3; c = (a + 1)/4; r = Range[1, 1500];
%t A191141 d = Intersection[b, r] (* A191206 *)
%t A191141 e = Intersection[c, r] (* A191207 *)
%o A191141 (Haskell)
%o A191141 import Data.Set (singleton, deleteFindMin, insert)
%o A191141 a191141 n = a191141_list !! (n-1)
%o A191141 a191141_list = f $ singleton 1
%o A191141    where f s = m : (f $ insert (3*m+2) $ insert (4*m-1) s')
%o A191141              where (m, s') = deleteFindMin s
%o A191141 -- _Reinhard Zumkeller_, Jun 01 2011
%Y A191141 Cf. A191113.
%K A191141 nonn
%O A191141 1,2
%A A191141 _Clark Kimberling_, May 28 2011