Abstract
A point P not on a non-degenerate conic C in PG(2, q), q odd, is called internal to C if no tangent line to C contains P, external otherwise. The set of internal points of C is a \(\frac{q(q-1)}{2}\)-set of type \((0,\frac{q-1}{2},\frac{q+1}{2})\). In this paper, we classify all \(\frac{q(q-1)}{2}\)-sets of class [0, m, n] having exactly two kinds of outer points.
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Innamorati, S., Zuanni, F. A characterization of the set of internal points of a conic in PG(2,q), q odd. J. Geom. 110, 19 (2019). https://doi.org/10.1007/s00022-019-0474-2
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DOI: https://doi.org/10.1007/s00022-019-0474-2