MathDB
Problems
Contests
National and Regional Contests
PEN Problems
PEN D Problems
8
8
Part of
PEN D Problems
Problems
(1)
D 8
Source:
5/25/2007
Characterize the set of positive integers
n
n
n
such that, for all integers
a
a
a
, the sequence
a
a
a
,
a
2
a^2
a
2
,
a
3
a^3
a
3
,
⋯
\cdots
⋯
is periodic modulo
n
n
n
.
Congruences