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Computing the equivariant Euler characteristic of Zariski and etale sheaves on curves

Bernhard Köck
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Abstract

We prove an equivariant Grothendieck-Ogg-Shafarevich formula. This formula may be viewed as an étale analogue of well-known formulas for Zariski sheaves generalizing the classical Chevalley-Weil formula. We give a new approach to those formulas (first proved by Ellingsrud/Lønsted, Nakajima, Kani and Ksir) which can also be applied in the étale case.

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Bernhard Köck. 2004-11-08. Computing the equivariant Euler characteristic of Zariski and etale sheaves on curves. https://arxiv.org/abs/math/0104212

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