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Gjergji Zaimi
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Intersection of pencils in $\mathcal{R}^2$

Consider $9n$ pencils through non-collinear points $p_1, \ldots , p_{9n}$ in $R^2$ each consisting of at most $n$ concurrent lines. Define the intersection $S$ of these pencils to be the set of points which lie on at least one line in each of the $9n$ pencils. Is it true that $|S|$ is $O(n)$?