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A191118 Increasing sequence generated by these rules: a(1)=1, and if x is in a then 3x-2 and 4x+3 are in a.

%I A191118 #12 Jul 13 2013 12:04:09
%S A191118 1,7,19,31,55,79,91,127,163,223,235,271,319,367,379,487,511,655,667,
%T A191118 703,811,895,943,955,1087,1099,1135,1279,1459,1471,1519,1531,1951,
%U A191118 1963,1999,2047,2107,2431,2623,2671,2683,2815,2827,2863,3247,3259,3295,3403,3583,3775,3823,3835,4351,4375,4399,4411,4543,4555,4591
%N A191118 Increasing sequence generated by these rules:  a(1)=1, and if x is in a then 3x-2 and 4x+3 are in a.
%C A191118 See A191113.
%H A191118 Reinhard Zumkeller, <a href="/A191118/b191118.txt">Table of n, a(n) for n = 1..10000</a>
%t A191118 h = 3; i = -2; j = 4; k = 3; f = 1; g = 9;
%t A191118 a = Union[Flatten[NestList[{h # + i, j # + k} &, f, g]]]  (* A191118 *)
%t A191118 b = (a + 2)/3; c = (a - 3)/4; r = Range[1, 1500];
%t A191118 d = Intersection[b, r] (* A191114 *)
%t A191118 e = Intersection[c, r] (* A191138 *)
%o A191118 (Haskell)
%o A191118 import Data.Set (singleton, deleteFindMin, insert)
%o A191118 a191118 n = a191118_list !! (n-1)
%o A191118 a191118_list = 1 : f (singleton 7)
%o A191118    where f s = m : (f $ insert (3*m-2) $ insert (4*m+3) s')
%o A191118              where (m, s') = deleteFindMin s
%o A191118 -- _Reinhard Zumkeller_, Jun 01 2011
%Y A191118 Cf. A191113.
%K A191118 nonn
%O A191118 1,2
%A A191118 _Clark Kimberling_, May 27 2011