MathDB
Problems
Contests
National and Regional Contests
PEN Problems
PEN J Problems
12
J 12
J 12
Source:
May 25, 2007
Divisor Functions
Problem Statement
Determine all positive integers
n
n
n
such that
n
=
d
(
n
)
2
n={d(n)}^2
n
=
d
(
n
)
2
.
Back to Problems
View on AoPS