OFFSET
1,2
EXAMPLE
n=13: 2^n=8192, trajectory ={8192, 8191, 26208, [20440], 20440, .. a[13]=8191 arose in transient.
MATHEMATICA
gf[x_] :=DivisorSigma[1, EulerPhi[x]] gite[x_, hos_] :=NestList[gf, x, hos] Table[Min[gite[2^w, 200]], {w, 1, 30}]
CROSSREFS
KEYWORD
nonn
AUTHOR
Labos Elemer, Jul 21 2004
STATUS
approved