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A remark on higher congruences for the number of rational points of varieties defined over a finite field

Hélène Esnault
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Abstract

We show that there is no simple congruence formula for the number of points of the mod p reduction of a regular model of a smooth proper variety defined over a local field with $\ell$-adic cohomology supported in codimension $\ge κ$.

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Hélène Esnault. 2005-07-16. A remark on higher congruences for the number of rational points of varieties defined over a finite field. https://arxiv.org/abs/math/0507331

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