Graphs That Admit 3-to-1 or 2-to-1 Maps onto the Circle
نویسندگان
چکیده
We give a complete and explicit characterization of the connected graphs which admit a continuous 3-to-1 map onto the circle, and of the connected graphs which admit a continuous 2-to-l map onto the circle. This generalizes earlier work of Heath and Hilton who considered the mappings of trees onto the circle.
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ورودعنوان ژورنال:
- Discrete Applied Mathematics
دوره 65 شماره
صفحات -
تاریخ انتشار 1996