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%I #9 Jul 13 2013 12:04:10
%S 1,2,5,9,14,21,26,37,41,57,62,77,85,105,110,122,149,165,170,185,229,
%T 230,249,254,309,314,329,341,365,421,441,446,489,494,509,554,597,661,
%U 681,686,689,741,746,761,917,921,926,941,986,997,1017,1022,1094,1237,1257,1262,1317,1322,1337,1365,1461,1466,1481,1526,1661,1685
%N Increasing sequence generated by these rules: a(1)=1, and if x is in a then 3x-1 and 4x+1 are in a.
%C See A191113.
%H Reinhard Zumkeller, <a href="/A191123/b191123.txt">Table of n, a(n) for n = 1..10000</a>
%t h = 3; i = -1; j = 4; k = 1; f = 1; g = 9;
%t a = Union[Flatten[NestList[{h # + i, j # + k} &, f, g]]] (* A191123 *)
%t b = (a + 1)/3; c = (a - 1)/4; r = Range[1, 1500];
%t d = Intersection[b, r] (* A191170 *)
%t e = Intersection[c, r] (* A191171 *)
%o (Haskell)
%o import Data.Set (singleton, deleteFindMin, insert)
%o a191123 n = a191123_list !! (n-1)
%o a191123_list = f $ singleton 1
%o where f s = m : (f $ insert (3*m-1) $ insert (4*m+1) s')
%o where (m, s') = deleteFindMin s
%o -- _Reinhard Zumkeller_, Jun 01 2011
%Y Cf. A191113.
%K nonn
%O 1,2
%A _Clark Kimberling_, May 27 2011
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