OFFSET
1,2
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10000
EXAMPLE
phi of the sequence includes 1, 512, 262144,.. etc.; powers arise several times; a(3) = A053576(9) = 771; in sequence smoother ranges and quite large jumps arise when power of new numbers appear as phi-values.
MATHEMATICA
k=9; Do[s=EulerPhi[n]^(1/k); If[IntegerQ[s], Print[n]], {n, 1, 10000000}]
PROG
(PARI) is(n)=ispower(eulerphi(n), 9) \\ Charles R Greathouse IV, Apr 24 2020
CROSSREFS
KEYWORD
nonn
AUTHOR
Labos Elemer, Nov 27 2002
STATUS
approved