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On unitals in \(PG(2,q^2)\) stabilized by a homology group

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Abstract

The linear collineation group of a classical unital of \(\mathrm{PG}(2,q^2)\) contains a group of homologies of order \(q+1\). In this paper we prove that if \(\mathcal{U }\) is a unital of PG\((2,q^2)\) stabilized by a homology group of order \(q+1\) and \(q\) is a prime number, then \(\mathcal{U }\) is classical.

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Correspondence to Nicola Durante.

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This is one of several papers published in Designs, Codes and Cryptography comprising the special topic on “Finite Geometries: A special issue in honor of Frank De Clerck”.

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Donati, G., Durante, N. & Siciliano, A. On unitals in \(PG(2,q^2)\) stabilized by a homology group. Des. Codes Cryptogr. 72, 135–139 (2014). https://doi.org/10.1007/s10623-013-9836-1

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  • DOI: https://doi.org/10.1007/s10623-013-9836-1

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