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arXiv · 2105.10994

On planar arcs of size $(q+3)/2$

Gülizar Günay·Michel Lavrauw
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Abstract

The subject of this paper is the study of small complete arcs in $\mathrm{PG}(2,q)$, for $q$ odd, with at least $(q+1)/2$ points on a conic. We give a short comprehensive proof of the completeness problem left open by Segre in his seminal work [20]. This gives an alternative to Pellegrino's long proof which was obtained in a series of papers in the 1980s. As a corollary of our analysis, we obtain a counterexample to a misconception in the literature [6].

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Gülizar Günay, Michel Lavrauw. 2021-05-23. On planar arcs of size $(q+3)/2$. https://arxiv.org/abs/2105.10994

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