OFFSET
1,2
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10000
EXAMPLE
63 is in the sequence because 63-phi(63) = 27, which is a cube.
MATHEMATICA
Select[Range[230], IntegerQ[(# - EulerPhi[ # ])^(1/3)] &] (* Stefan Steinerberger, Apr 24 2006 *)
PROG
(PARI) isok(k) = ispower(k-eulerphi(k), 3); \\ Michel Marcus, Mar 23 2021
CROSSREFS
KEYWORD
nonn
AUTHOR
Luc Stevens (lms022(AT)yahoo.com), Apr 23 2006
STATUS
approved