On some points-and-lines problems and configurations
نویسندگان
چکیده
منابع مشابه
On some points-and-lines problems and configurations
We apply an old method for constructing points-and-lines configurations in the plane to study some recent questions in incidence geometry. What are known as “Points and Lines” puzzles are found very interesting by many people. The most familiar example, here given, to plant nine trees so that they shall form ten straight rows with three trees in every row, is attributed to Sir Isaac Newton, but...
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Small Triangle-Free Configurations of Points and Lines
In the paper we show that all combinatorial triangle-free configurations for v ≤ 18 are geometrically realizable. We also show that there is a unique smallest astral (183) triangle-free configuration and its Levi graph is the generalized Petersen graph G(18, 5). In addition, we present geometric realizations of the unique flag transitive triangle-free configuration (203) and the unique point tr...
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ژورنال
عنوان ژورنال: Periodica Mathematica Hungarica
سال: 2006
ISSN: 0031-5303,1588-2829
DOI: 10.1007/s10998-006-0027-y