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Vojtěch Jarník IMC
2000 VJIMC
Problem 3
Problem 3
Part of
2000 VJIMC
Problems
(2)
limits equal for bounded sequence of reals
Source: VJIMC 2000 1.3
7/26/2021
Let
a
1
,
a
2
,
…
a_1,a_2,\ldots
a
1
,
a
2
,
…
be a bounded sequence of reals. Is it true that the fact
lim
N
→
∞
1
N
∑
n
=
1
N
a
n
=
b
and
lim
N
→
∞
1
log
N
∑
n
=
1
N
a
n
n
=
c
\lim_{N\to\infty}\frac1N\sum_{n=1}^Na_n=b\enspace\text{ and }\enspace\lim_{N\to\infty}\frac1{\log N}\sum_{n=1}^N\frac{a_n}n=c
N
→
∞
lim
N
1
n
=
1
∑
N
a
n
=
b
and
N
→
∞
lim
lo
g
N
1
n
=
1
∑
N
n
a
n
=
c
implies
b
=
c
b=c
b
=
c
?
limits
real analysis
Czech Republic 2000
Source:
6/6/2015
Prove that if m,n are nonnegative integers and 0<=x<=1 then
(
1
−
x
n
)
m
+
(
1
−
(
1
−
x
)
m
)
n
≥
1
(1-x^n)^m + (1-(1-x)^m)^n \ge 1
(
1
−
x
n
)
m
+
(
1
−
(
1
−
x
)
m
)
n
≥
1
inequalities
function