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Miklós Schweitzer
1995 Miklós Schweitzer
9
9
Part of
1995 Miklós Schweitzer
Problems
(1)
serpentine in compact set
Source: miklos schweitzer 1995 q9
10/5/2021
A serpentine is a sequence of points
P
1
,
.
.
.
,
P
m
P_1 , ..., P_m
P
1
,
...
,
P
m
in a plane, not necessarily all different, such that the distance between
P
i
P_i
P
i
and
P
i
+
1
P_{i+1}
P
i
+
1
is at least 1, and the segments
P
i
P
i
+
1
P_i P_{i +1}
P
i
P
i
+
1
are alternately horizontal and vertical. Construct a compact set in which there is a sequence of serpentines with arbitrary long lengths but there is no closed serpentine (
P
m
=
P
i
P_m = P_i
P
m
=
P
i
for some i < m).
real analysis