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%I #5 Mar 30 2012 17:22:55
%S 4,10,13,28,40,82,91,121,146,182,205,244,328,364,386,656,671,730,757,
%T 820,949,1036,1093,1342,1640,2044,2188,2362,2555,2644,2684,2812,2920,
%U 3280,3640,3796,3851,4088,4561,4745,5110,6176,6562,6643,7381,7592,7913
%N Primitive numbers k such that m/k is in the Cantor set for some m.
%C Primitive means no k is a multiple of 3. This is sequence A054591 without the multiples of 3. Sequence A173793 is a subsequence. Sequence A173932 gives the least m such for each k. Sequence A173933 gives the number of m < k/2 such that m/k is in the Cantor set. Irregular triangle A173934 gives a row of m values for each k.
%C The remaining terms <10000 are 9139, 9490, 9841.
%C It is assumed that gcd(m,k) = 1.
%H T. D. Noe, <a href="/A173931/b173931.txt">Table of n, a(n) for n=1..185</a>
%t InCantorQ[m_, n_] := !MemberQ[Union[Flatten[RealDigits[m/n,3][[1]]]], 1]; cantor=Reap[Do[If[Mod[n,3] > 0, s=Select[Range[Ceiling[n/2]], GCD[n,# ]==1 && InCantorQ[ #,n] &]; If[s != {}, Sow[{n, s}]]], {n,10000}]][[2,1]]; First[Transpose[cantor]]
%K nonn
%O 1,1
%A _T. D. Noe_, Mar 03 2010
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