Abstract
In this paper we remove the solid incidence assumption in the characterization of J. Schillewaert (A characterization of quadrics by intersection numbers, Des. Codes Cryptogr., 47 (2008), 165–175) by proving that quadric plane incidence numbers imply quadric solid incidence numbers, except for the dual complete 11-cap of PG(4, 3). Furthermore, new characterizations of the parabolic quadric Q(4, q) and the ovoidal cone of PG(4, q) are provided.
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We are grateful to the three anonymous referees for their useful suggestions which greatly improved the presentation of this paper.
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Dedicated to Prof. Osvaldo Ferri on the occasion of his 85th birthday.
Remembering Prof. Giuseppe Tallini on the 25th anniversary of his death.
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Innamorati, S., Zuanni, F. Classifying sets of class \([1,q+1,2q+1,q^2+q+1]_2\) in PG(r, q), \(r\ge 3\). Des. Codes Cryptogr. 89, 489–496 (2021). https://doi.org/10.1007/s10623-020-00833-9
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DOI: https://doi.org/10.1007/s10623-020-00833-9