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Putnam
1964 Putnam
B1
Putnam 1964 B1
Putnam 1964 B1
Source: Putnam 1964
March 5, 2022
Putnam
Convergence
Problem Statement
Let
u
k
u_k
u
k
be a sequence of integers, and let
V
n
V_n
V
n
be the number of those which are less than or equal to
n
n
n
. Show that if
∑
k
=
1
∞
1
u
k
<
∞
,
\sum_{k=1}^{\infty} \frac{1}{u_k } < \infty,
k
=
1
∑
∞
u
k
1
<
∞
,
then
lim
n
→
∞
V
n
n
=
0.
\lim_{n \to \infty} \frac{ V_{n}}{n}=0.
n
→
∞
lim
n
V
n
=
0.
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