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2014 IMS
8
Is it convergent?
Is it convergent?
Source: IMS 2014 - Day2 - Problem8
October 4, 2014
trigonometry
real analysis
real analysis unsolved
Problem Statement
Is
∑
n
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∞
cos
n
n
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2
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⋯
+
1
n
)
\sum_{n=1}^{+\infty}\frac{\cos n}{n}(1 + \frac{1}{\sqrt{2}} + \cdots + \frac{1}{\sqrt{n}})
∑
n
=
1
+
∞
n
c
o
s
n
(
1
+
2
1
+
⋯
+
n
1
)
convergent? why?
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