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arXiv · 1303.7046

Ramified coverings of small categories

Kazunori Noguchi
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Abstract

We introduce a ramified covering of small categories, and we show three properties of the notion: the Riemann-Hurwitz formula holds for a ramified covering of finite categories, the zeta function of $C$ divides that of $\widetilde{C}$ for a ramified covering $\map{P}{\widetilde{C}}{C}$ of finite categories, and the classifying space of a $d$-fold ramified covering of small categories is also a $d$-fold ramified covering in the sense of Dold \cite{Dol86}.

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Kazunori Noguchi. 2013-03-28. Ramified coverings of small categories. https://arxiv.org/abs/1303.7046

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