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%I #11 Jul 13 2013 12:04:11
%S 1,5,17,21,53,65,69,85,161,197,209,213,257,261,277,341,485,593,629,
%T 641,645,773,785,789,833,837,853,1025,1029,1045,1109,1365,1457,1781,
%U 1889,1925,1937,1941,2321,2357,2369,2373,2501,2513,2517,2561,2565,2581,3077,3089,3093,3137,3141,3157,3329,3333,3349,3413,4097,4101
%N 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 See A191113.
%H Reinhard Zumkeller, <a href="/A191143/b191143.txt">Table of n, a(n) for n = 1..10000</a>
%t h = 3; i = 2; j = 4; k = 1; f = 1; g = 9;
%t a = Union[Flatten[NestList[{h # + i, j # + k} &, f, g]]] (* A191143 *)
%t b = (a - 2)/3; c = (a - 1)/4; r = Range[1, 1500];
%t d = Intersection[b, r] (* A191210 *)
%t e = Intersection[c, r] (* A191136 *)
%t m = (a + 1)/2 (* divisibility property *)
%t p = (a + 3)/4 (* divisibility property *)
%o (Haskell)
%o import Data.Set (singleton, deleteFindMin, insert)
%o a191143 n = a191143_list !! (n-1)
%o a191143_list = f $ singleton 1
%o where f s = m : (f $ insert (3*m+2) $ 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 28 2011
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