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Canada National Olympiad
2022 Canada National Olympiad
2
2
Part of
2022 Canada National Olympiad
Problems
(1)
number theory
Source: Canadian MO 2022
3/11/2022
I think we are allowed to discuss since its after 24 hours How do you do this Prove that
d
(
1
)
+
d
(
3
)
+
.
.
+
d
(
2
n
−
1
)
≤
d
(
2
)
+
d
(
4
)
+
.
.
.
d
(
2
n
)
d(1)+d(3)+..+d(2n-1)\leq d(2)+d(4)+...d(2n)
d
(
1
)
+
d
(
3
)
+
..
+
d
(
2
n
−
1
)
≤
d
(
2
)
+
d
(
4
)
+
...
d
(
2
n
)
which
d
(
x
)
d(x)
d
(
x
)
is the divisor function
number theory