Three-point sets
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Khalid Bouhjar; Jan J. Dijkstra; Jan van Mill
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Article
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2001
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Elsevier Science
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English
⚖ 161 KB
We prove that a planar set which meets each line in exactly three points cannot contain a continuum and cannot be an F σ -set. We also present some results on extending and splitting n-point sets. Our results imply that there is a four-point set which contains an arc.