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Putnam
1971 Putnam
B6
B6
Part of
1971 Putnam
Problems
(1)
Putnam 1971 B6
Source:
4/6/2022
Let
δ
(
x
)
\delta (x)
δ
(
x
)
be the greatest odd divisor of the positive integer
x
x
x
. Show that
∣
∑
n
=
1
x
δ
(
n
)
/
n
−
2
x
/
3
∣
<
1
,
| \sum_{n=1}^x \delta (n)/n -2x/3| <1,
∣
∑
n
=
1
x
δ
(
n
)
/
n
−
2
x
/3∣
<
1
,
for all positive integers
x
.
x.
x
.
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