Polynomial overrings of $\mathrm{Int}(\mathbb Z)$
Polynomial overrings of $\mathrm{Int}(\mathbb Z)$
We show that every polynomial overring of the ring $\mathrm{Int}(\mathbb Z)$ of polynomials which are integer-valued over $\mathbb Z$ may be considered as the ring of polynomials which are integer-valued over some subset of $\mathbb{\widehat Z}$, the profinite completion of $\mathbb Z$ with respect to the fundamental system of neighbourhoods …