login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A077096 Starting iteration of Phi[]*(Sigma[]-Phi[]) function at these initial values leads to the fixed point 8064. 0
7530, 8064, 9678, 9828, 9990, 10002, 10290, 10464, 11000, 11004, 11172, 11350, 11510, 11572, 11814, 11930, 12006, 12192, 12348, 12472, 12636, 12654, 12726, 12750, 12772, 12972, 13332, 13372, 13420, 13440, 13626, 13648, 13656, 13695 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..34.

EXAMPLE

n=41354: FixedPointList={41354,13440,15232,8064},end=8064.

MATHEMATICA

f[x_] := EulerPhi[DivisorSigma[1, x]-EulerPhi[x]] Do[s=NestList[f, n, 100]; s1=Part[s, 99]; s2=Part[s, 100]; If[Equal[s1, s2]&&Equal[s1, 8064], Print[n]], {n, 1, 1000000}]

fp[n_]:=FixedPoint[EulerPhi[DivisorSigma[1, #]-EulerPhi[#]]&, n, 100]==8064; Select[ Range[14000], fp] (* Harvey P. Dale, May 05 2013 *)

CROSSREFS

Cf. A077090-A077100.

Sequence in context: A273382 A186938 A185749 * A031137 A210171 A234987

Adjacent sequences:  A077093 A077094 A077095 * A077097 A077098 A077099

KEYWORD

nonn

AUTHOR

Labos Elemer, Oct 31 2002

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified May 21 11:28 EDT 2022. Contains 353908 sequences. (Running on oeis4.)