The T (4) Property of Families of Unit Disks
نویسنده
چکیده
For a family F of n mutually disjoint unit disks in the plane, we show that if any four disks are intersected by a line then there is a line that intersects at least n− 1 disks of F .
منابع مشابه
A Transversal Property of Families of Eight or Nine Unit Disks
For a family F of n disjoint unit disks in the plane with the property T (4), we show that if there is an (n − 2)-transversal that strictly separates two elements of F then F has the property T − 1; that is, it has an (n − 1)-transversal. We apply this generic result to verify that T (4) implies T − 1 for families F of eight or nine disks.
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