منابع مشابه
On sets without tangents and exterior sets of a conic
A set without tangents in PG(2, q) is a set of points S such that no line meets S in exactly one point. An exterior set of a conic C is a set of points E such that all secant lines of E are external lines of C. In this paper, we first recall some known examples of sets without tangents and describe them in terms of determined directions of an affine pointset. We show that the smallest sets with...
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ژورنال
عنوان ژورنال: Fundamenta Mathematicae
سال: 1934
ISSN: 0016-2736,1730-6329
DOI: 10.4064/fm-22-1-49-53