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On the geometry of full points of abstract unitals

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Abstract

The concept of full points of abstract unitals has been introduced by Korchmáros, Siciliano and Szőnyi as a tool for the study of projective embeddings of abstract unitals. In this paper we give a detailed description of the combinatorial and geometric structure of the sets of full points in abstract unitals of finite order.

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Acknowledgements

The authors would like to thank the referees for their valuable remarks and suggestions.

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Correspondence to Gábor P. Nagy.

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Communicated by G. Korchmaros.

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Support provided from the National Research, Development and Innovation Fund of Hungary, financed under the 2018-1.2.1-NKP funding scheme, within the SETIT Project 2018-1.2.1-NKP-2018-00004. Partially supported by OTKA Grants 119687 and 115288.

Appendix A: Unital of order 4 with non-cyclic embedded dual 3-net

Appendix A: Unital of order 4 with non-cyclic embedded dual 3-net

figure a

The output of the last command is “S5”, showing that the group of perspectivities is not cyclic.

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Mezőfi, D., Nagy, G.P. On the geometry of full points of abstract unitals. Des. Codes Cryptogr. 87, 2967–2978 (2019). https://doi.org/10.1007/s10623-019-00658-1

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