arXiv · 2109.07214
It is established that any homeomorphism between two closed negligible subset of $D^\tau$ can be extended to an autohomeomorphism of $D^\tau$.
E. Shchepin, V. Valov. 2021-09-15. On homogeneity of Cantor cubes. https://doi.org/10.13140/rg.2.2.34061.05601
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We investigate the finite ultrametric spaces $(X,d)$ that have a given cardinality of the center of distances and a minimal cardinality of the set $X$. It is shown that such spaces are isometric if and only if their centers of distances are the same. The representing trees of these spaces are characterized up to isomorphism.
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