On the diameter of the rotation graph of binary coupling trees
نویسندگان
چکیده
A binary coupling tree on n + 1 leaves is a binary tree in which the leaves have distinct labels. The rotation graph Gn is defined as the graph of all binary coupling trees on n+1 leaves, with edges connecting trees that can be transformed into each other by a single rotation. In this paper we study distance properties of the graph Gn. Exact results for the diameter of Gn for values up to n = 10 are obtained. For larger values of n we prove upper and lower bounds for the diameter, which yield the result that the diameter of Gn grows like n lg(n).
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ورودعنوان ژورنال:
- Discrete Mathematics
دوره 245 شماره
صفحات -
تاریخ انتشار 2002