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A098191
The values within a cycle of length 53 of the map x->A098189(x), sorted.
7
1500, 1570, 1714, 1718, 1722, 1768, 2062, 2066, 2070, 2084, 2120, 2220, 2276, 2328, 2348, 2578, 2582, 2586, 2760, 3218, 3222, 3328, 3428, 3552, 3704, 3736, 3792, 3864, 3984, 4192, 4324, 4332, 4400, 4480, 4656, 5088, 5128, 5464, 5544, 5856, 5872, 6200
OFFSET
1,1
COMMENTS
See various attractors in A098191-A098195.
LINKS
Michael De Vlieger, Table of n, a(n) for n = 1..53
EXAMPLE
The map has a trajectory 1500->2120->2084->1570->...->6660->9672->13248->11376->..->1768->1500 (returning
to the first term). The sequence contains all 53 members of this individual cycle, resorted to increasing magnitude.
MATHEMATICA
Union@ NestList[Function[n, DivisorSum[n, # &, CoprimeQ[#, n/#] &] - EulerPhi@ n], 1500, 53] (* Michael De Vlieger, Mar 01 2017 *)
CROSSREFS
KEYWORD
nonn,fini
AUTHOR
Labos Elemer, Sep 03 2004
EXTENSIONS
Edited by R. J. Mathar, Mar 02 2009
STATUS
approved