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A168146 Numbers n such that phi(n) > pi(n). 1
1, 5, 7, 9, 11, 13, 15, 16, 17, 19, 21, 22, 23, 25, 26, 27, 28, 29, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Numbers n such that A000010(n) > A000720(n).

LINKS

G. C. Greubel, Table of n, a(n) for n = 1..1000

FORMULA

A000010(a(n)) > A000720(a(n)).

A000027 \ A037229. - R. J. Mathar, Nov 19 2009

EXAMPLE

A000010(a(1)=1)=1>A000720(a(1)=1)=0; A000010(a(2)=5)=4>A000720(a(2)=5)=3.

MATHEMATICA

Select[Range[100], EulerPhi[#]>PrimePi[#]&] (* Harvey P. Dale, Jun 03 2016 *)

CROSSREFS

Cf. A000010, A000720, A037121, A037228, A037229 (complement), A073456.

Sequence in context: A325797 A128163 A177088 * A106505 A097985 A099047

Adjacent sequences:  A168143 A168144 A168145 * A168147 A168148 A168149

KEYWORD

nonn

AUTHOR

Juri-Stepan Gerasimov, Nov 19 2009

EXTENSIONS

More terms from R. J. Mathar, Nov 19 2009

STATUS

approved

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Last modified February 21 20:34 EST 2020. Contains 332111 sequences. (Running on oeis4.)