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On trees covering chains or stars

F. Pakovich
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Abstract

In this paper, in the context of the ``Dessins d'enfants'' theory, we give a combinatorial criterion for a plane tree to cover a tree from the classes of "chains" or "stars''. Besides, we discuss some applications of this result which are related to the arithmetical theory of torsion on curves.

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F. Pakovich. 2008-01-15. On trees covering chains or stars. https://arxiv.org/abs/math/0401201

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