%I A089684
%S A089684 1,3,5,7,9,11,13,15,17,19,21,23,25,27,29,31,33,35,37,39,41,43,45,47,
%T A089684 49,51,53,55,57,59,61,63,65,67,69,71,73,75,77,79,81,83,85,87,89,91,
%U A089684 93,95,97,99,101,103,107,109,111,113,115,117,119,121,123,125,127
%N A089684 Numbers n such that 2*phi(n) > n.
%F A089684 Asymptotic to c*n with c=2.045...
%t A089684 lst={}; Do[If[2*EulerPhi[n]>n, AppendTo[lst, n]], {n, 200}]; lst (T.
D. Noe)
%t A089684 Select[ Range[130], 2EulerPhi[ # ] > # &] (from Robert G. Wilson v Jan
16 2004)
%Y A089684 Cf. A036798, A067800 (composite n such that 2 phi(n) > n).
%Y A089684 Cf. A036798, the missing odd numbers.
%Y A089684 Sequence in context: A005408 A144396 A060747 this_sequence A105356 A082453
A033041
%Y A089684 Adjacent sequences: A089681 A089682 A089683 this_sequence A089685 A089686
A089687
%K A089684 nonn
%O A089684 1,2
%A A089684 Benoit Cloitre, Jan 16 2004
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