Ifu is a terminal node of a rooted tree T. with n terminal nodes, let h(u) = ~f (d(v)) where the sum is over all interior nodes v in the path from the root of T. to u, d(v) is the out-degree of v, and 1" is a non-negative cost function. The path entropy function h(T.) = ~h(u), where the sum is over
On Reconstructing Rooted Trees
β Scribed by T. Andreae
- Publisher
- Elsevier Science
- Year
- 1994
- Tongue
- English
- Weight
- 667 KB
- Volume
- 62
- Category
- Article
- ISSN
- 0095-8956
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β¦ Synopsis
A probably very difficult question of Nash-Williams asks whether any two hypomorphic trees are isomorphic. In the present paper, we consider rooted trees rather than trees and give an affirmative answer to the corresponding version of Nash-Williams' question, i.e., we show that any two hypomorphic rooted trees are isomorphic. Further related results are given, together with applications to the reconstruction of unrooted trees. (\mathbb{C} 1994) Academic Press, Inc.
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