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PEN Problems
PEN J Problems
22
22
Part of
PEN J Problems
Problems
(1)
J 22
Source:
5/25/2007
Let
n
n
n
be an odd positive integer. Prove that
σ
(
n
)
3
<
n
4
\sigma(n)^3 <n^4
σ
(
n
)
3
<
n
4
.
inequalities
Divisor Functions