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arXiv · 1508.03688

\v{C}ech complexes for covers of small categories

Kohei Tanaka
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Abstract

We present a combinatorial analogue of the nerve theorem for covers of small categories, using the Grothendieck construction. We apply our result to prove the inclusion-exclusion principle for the Euler characteristic of a finite category.

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Kohei Tanaka. 2015-08-15. \v{C}ech complexes for covers of small categories. https://arxiv.org/abs/1508.03688

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