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%I A067800 #26 Aug 29 2021 19:18:09
%S A067800 1,9,15,21,25,27,33,35,39,45,49,51,55,57,63,65,69,75,77,81,85,87,91,
%T A067800 93,95,99,111,115,117,119,121,123,125,129,133,135,141,143,145,147,153,
%U A067800 155,159,161,169,171,175,177,183,185,187,189,201,203,205,207,209,213,215
%N A067800 Nonprime n such that phi(n) > n/2.
%C A067800 Sequence is similar to A014076(n) giving odd nonprimes. Only 3 terms = 105, 165, 195 are not in the sequence among 59 terms < 210.
%C A067800 Cototient[m] > totient[m] equivalent to 2phi[m] < m; the missing terms mentioned here seem to form A036798. - _Labos Elemer_, May 08 2003
%C A067800 The number 9075 is not in this sequence, is in A014076 and is not in A036798, which means that the missing terms mentioned here do not form A036798 (cf. A118700). - _R. J. Mathar_, Aug 08 2007
%t A067800 Select[Range[250],!PrimeQ[#]&&EulerPhi[#]>#/2&] (* _Harvey P. Dale_, Aug 29 2021 *)
%Y A067800 Cf. A036798, A083254.
%K A067800 nonn
%O A067800 1,2
%A A067800 _Benoit Cloitre_, Feb 07 2002

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