If $\mathcal{E}$ is a Grothendieck topos, is it known whether one can always find a small site $(\mathbb{C}, \mathcal{J})$ with $\mathcal{E} \simeq \mathsf{Sh}(\mathbb{C}, \mathcal{J})$ and the topology $\mathcal{J}$ is generated by (or even contains) only singleton families, in the sense that $\mathcal{J}$ is generated by a pretopology or coverage consisting of just singleton families?
2026-03-25 18:54:49.1774464889
Can any Grothendieck topos be presented by a singleton coverage?
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