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On Mathon's construction of maximal arcs in Desarguesian planes. II

Frank Fiedler·Ka Hin Leung·Qing Xiang
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Abstract

In a recent paper [M], Mathon gives a new construction of maximal arcs which generalizes the construction of Denniston. In relation to this construction, Mathon asks the question of determining the largest degree of a non-Denniston maximal arc arising from his new construction. In this paper, we give a nearly complete answer to this problem. Specifically, we prove that when $m\geq 5$ and $m\neq 9$, the largest $d$ of a non-Denniston maximal arc of degree $2^d$ in PG(2,2^m) generated by a {p,1}-map is $(\floor {m/2} +1)$. This confirms our conjecture in [FLX]. For {p,q}-maps, we prove that if $m\geq 7$ and $m\neq 9$, then the largest $d$ of a non-Denniston maximal arc of degree $2^d$ in PG(2,2^m) generated by a {p,q}-map is either $\floor {m/2} +1$ or $\floor{m/2} +2$.

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Frank Fiedler, Ka Hin Leung, Qing Xiang. 2004-01-05. On Mathon's construction of maximal arcs in Desarguesian planes. II. https://arxiv.org/abs/math/0401030

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