Non-isomorphic caterpillars with identical subtree data
نویسندگان
چکیده
The greedoid Tutte polynomial of a tree is equivalent to a generating function that encodes information about the number of subtrees with I internal (non-leaf) edges and L leaf edges, for all I and L. We prove that this information does not uniquely determine the tree T by constructing an infinite family of pairs of non-isomorphic caterpillars, each pair having identical subtree data. This disproves conjectures of [2] and [6] and contrasts with the situation for rooted trees, where this data completely determines the rooted tree.
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ورودعنوان ژورنال:
- Discrete Mathematics
دوره 306 شماره
صفحات -
تاریخ انتشار 2006