Denote by \(S_{n}\) the set of all distinct rooted binary trees with \(n\) unlabeled vertices. Define \(\sigma_{n}\) as a total height of a tree chosen at random in the set \(S_{n}\), assuming that all the possible choices are equally probable. The total height of a tree is defined as the sum of the
On the Automorphism Group of the One-Rooted Binary Tree
β Scribed by A.M. Brunner; Said Sidki
- Publisher
- Elsevier Science
- Year
- 1997
- Tongue
- English
- Weight
- 339 KB
- Volume
- 195
- Category
- Article
- ISSN
- 0021-8693
No coin nor oath required. For personal study only.
β¦ Synopsis
Let A be the automorphism group of the one-rooted regular binary tree T and 2 G the subgroup of A consisting of those automorphisms admitting a ''finite Ε½ . description'' in their action on T . Let N G be the normaliser of G in A, let 2 A Ε½ . Ε½ . Aut G be the group of automorphisms of G, and let End G be the semigroup of A endomorphisms of G induced by conjugation by elements of A. Then G is the Ε½ . infinite iterated wreath product . . . X C X C , and A is the topological limit of 2 2
Ε½ . Ε½ . G. We study in some detail the structure of G, Aut G , and End G . In A Ε½ .
Ε½ . particular, we prove N G is isomorphic to Aut G , contains a copy of A itself, A Ε½ . and is a proper subgroup of End G . Furthermore we discuss connections with A automata and introduce the notion of functionally recursive automorphisms of T .
2
π SIMILAR VOLUMES
In this paper, we prove that there are no automorphism orbits of the Kohn-Nirenberg domain accumulating at the origin.  2002 Elsevier Science (USA)
Let be a graph and let G be a subgroup of automorphisms of . Then G is said to be locally primitive on if, for each vertex v, the stabilizer G v induces a primitive group of permutations on the set of vertices adjacent to v. This paper investigates pairs G for which G is locally primitive on , G is