Let $C(r)$ be the origin-centered circle of radius $r$, and let $\beta(r)$ be the *exterior buffer* around $C(r)$: the distance from $C(r)$ to the closest lattice point exterior to $C(r)$: <br /> ![BetaBuffer][1]<br /> For example, $\beta(2) = \sqrt{5}-2 \approx 0.24$ because there are no lattice points strictly between $C(2)$ and $C(\sqrt{5})$, and this is the largest buffer around $C(2)$. I am interested in the behavior of $\beta(r)$ for large $r \in \mathbb{R}$, as I believe understanding that behavior will answer my question concerning *ratchet spirals*, [Lattice radial-step (ratchet) spirals][2]. I'll pose a specific question before formulating the general question. > **Q1**. Is there an $R$ such that, for all $r > R$, $\beta(r) < \frac{1}{2}$ ? If so, then, for example, the spiral $S(3,\frac{1}{2})$ depicted in that question is unbounded. > **Q2**. Is there an $R(\epsilon)$ such that, for all $r > R(\epsilon)$, $\beta(r) < \epsilon$, where $0 < \epsilon < 1$ ? [1]: https://i.sstatic.net/nrW9t.jpg [2]: https://mathoverflow.net/q/145963/6094