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Miklós Schweitzer
1994 Miklós Schweitzer
5
5
Part of
1994 Miklós Schweitzer
Problems
(1)
analysis
Source: miklos schweitzer 1994 q5
10/16/2021
Let H be a
G
δ
G_{\delta}
G
δ
subset of
R
\mathbb R
R
whose closure has a positive Lebesgue measure. Prove that the set
H
+
H
+
H
+
H
=
{
x
+
y
+
z
+
u
:
x
,
y
,
z
,
u
∈
H
}
H + H + H + H = \{ x + y + z + u : x , y , z , u \in H \}
H
+
H
+
H
+
H
=
{
x
+
y
+
z
+
u
:
x
,
y
,
z
,
u
∈
H
}
contains an interval.
real analysis
Measure theory