Proper and Unit Tolerance Graphs
نویسندگان
چکیده
We answer a question of Golumbic, Monma and Trotter by constructing proper tolerance graphs that are not unit tolerance graphs. An infinite family of graphs that are minimal in this respect is specified.
منابع مشابه
Proper and unit bitolerance orders and graphs
We say any order ~ is a tolerance order on a set of vertices if we may assign to each vertex x an interval Ix of real numbers and a real number tx called a tolerance in such a way that x~,y if and only if the overlap of Ix and ly is less than the minimum of t~ and ty and the center of I~ is less than the center of Iy. An order is a bitolerance order if and only if there are intervals Ix and rea...
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ورودعنوان ژورنال:
- Discrete Applied Mathematics
دوره 60 شماره
صفحات -
تاریخ انتشار 1995