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Miklós Schweitzer
1971 Miklós Schweitzer
5
Miklos Schweitzer 1971_5
Miklos Schweitzer 1971_5
Source:
October 29, 2008
real analysis
real analysis unsolved
Problem Statement
Let
λ
1
≤
λ
2
≤
.
.
.
\lambda_1 \leq \lambda_2 \leq...
λ
1
≤
λ
2
≤
...
be a positive sequence and let
K
K
K
be a constant such that
∑
k
=
1
n
−
1
λ
k
2
<
K
λ
n
2
(
n
=
1
,
2
,
.
.
.
)
.
\sum_{k=1}^{n-1} \lambda^2_k < K \lambda^2_n \;(n=1,2,...).
k
=
1
∑
n
−
1
λ
k
2
<
K
λ
n
2
(
n
=
1
,
2
,
...
)
.
Prove that there exists a constant
K
′
K'
K
′
such that
∑
k
=
1
n
−
1
λ
k
<
K
′
λ
n
(
n
=
1
,
2
,
.
.
.
)
.
\sum_{k=1}^{n-1} \lambda_k < K' \lambda_n \;(n=1,2,...).
k
=
1
∑
n
−
1
λ
k
<
K
′
λ
n
(
n
=
1
,
2
,
...
)
.
L. Leindler
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