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arXiv · 2611.08890

A counterexample to Manin's Conjecture for almost Fano varieties

Brian Lehmann·Sho Tanimoto
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Abstract

We give an example of a smooth rational threefold over a number field with a big anticanonical divisor that does not satisfy the thin set version of Manin's Conjecture. In particular, Manin's Conjecture does not hold for rationally connected almost Fano varieties.

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Brian Lehmann, Sho Tanimoto. 2026-11-06. A counterexample to Manin's Conjecture for almost Fano varieties. https://arxiv.org/abs/2611.08890

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