2 problems

Let $X$ be a regular connected scheme, flat and proper over $\operatorname{Spec}({\mathbb Z})$, with generic fibre $X\otimes_{\mathbb Z}{\mathbb Q}$ projective over ${\mathbb Q}$.…

Let $X$ be an arithmetic scheme. Its counting function $N(t)$ satisfies $N(1)=\chi_{\mathrm{abs}}(X)$, the absolute Euler characteristic. An absolute Euler product is an infinite p…