OFFSET
1,2
COMMENTS
It contains the sequence A003277 (cyclic numbers).
LINKS
Charles R Greathouse IV, Table of n, a(n) for n = 1..10000
MATHEMATICA
Select[Range[300], PowerMod[EulerPhi[#], EulerPhi[#], #] == GCD[#,
EulerPhi[#]] &]
PROG
(PARI) is(n)=my(p=eulerphi(n), g=gcd(p, n)); Mod(p, n)^p==g \\ Charles R Greathouse IV, Dec 27 2013
CROSSREFS
KEYWORD
nonn
AUTHOR
José María Grau Ribas, Nov 01 2013
STATUS
approved