

A067800


Nonprime n such that phi(n) > n/2.


4



1, 9, 15, 21, 25, 27, 33, 35, 39, 45, 49, 51, 55, 57, 63, 65, 69, 75, 77, 81, 85, 87, 91, 93, 95, 99, 111, 115, 117, 119, 121, 123, 125, 129, 133, 135, 141, 143, 145, 147, 153, 155, 159, 161, 169, 171, 175, 177, 183, 185, 187, 189, 201, 203, 205, 207, 209, 213, 215
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OFFSET

1,2


COMMENTS

Sequence is similar to A014076(n) giving odd nonprimes. Only 3 terms = 105, 165, 195 are not in the sequence among 59 terms < 210.
Cototient[m] > totient[m] equivalent to 2phi[m] < m; the missing terms mentioned here seem to form A036798.  Labos Elemer, May 08 2003
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


LINKS

Table of n, a(n) for n=1..59.


CROSSREFS

Cf. A036798, A083254.
Sequence in context: A270574 A071904 A014076 * A155474 A100819 A046446
Adjacent sequences: A067797 A067798 A067799 * A067801 A067802 A067803


KEYWORD

nonn


AUTHOR

Benoit Cloitre, Feb 07 2002


STATUS

approved



