On degrees of vertices in paradoxical trees
نویسندگان
چکیده
We present some necessary and su cient conditions (in terms of degrees of vertices) for locally nite tree T=(V; E) to be paradoxical, i.e. to have a partition V=V1∪V2 and one-to-one mappings fi :V → Vi; i=1; 2 such that the supremum of the distances between v and fi(v) over v ∈ V and i = 1; 2 is nite. c © 2000 Published by Elsevier Science B.V. All rights reserved.
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عنوان ژورنال:
- Discrete Mathematics
دوره 212 شماره
صفحات -
تاریخ انتشار 2000