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A183213 Ordering of the numbers in the set S generated by these rules: 1 is in S, and if n is in S, then floor[(3n-1)/2] and 3n are in S. 3

%I #11 May 25 2015 16:40:43

%S 1,3,4,5,7,9,10,12,13,14,15,17,19,20,21,22,25,27,28,29,30,31,32,36,37,

%T 39,40,41,42,43,44,45,46,47,51,53,55,57,58,59,60,61,62,63,64,65,66,67,

%U 68,70,75,76,79,81,82,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,100,101,104,108,111,112,113,117,118,120,121,122,123,125,126,127,128,129,130,131,132,133,134,135

%N Ordering of the numbers in the set S generated by these rules: 1 is in S, and if n is in S, then floor[(3n-1)/2] and 3n are in S.

%C This sequence results from flattening and sorting the tree at A183211. Complement of A178931, obtained from the tree at A183212.

%H Ivan Neretin, <a href="/A183213/b183213.txt">Table of n, a(n) for n = 1..10000</a>

%F (See the Mathematica code.)

%t nn=200; t={1}; t0=t; While[t=Select[Union[t,Floor[(3*t-1)/2],3*t], #<=nn &]; t0 != t, t0=t]; t

%t f[s_List] := Select[ Union@ Join[s, Floor[(3 s - 1)/2], 3 s], # < 201 &]; NestWhile[f, {1}, UnsameQ, All]

%Y Cf. A183211, A178931.

%K nonn

%O 1,2

%A _Clark Kimberling_, Dec 30 2010

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