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arXiv · 2504.05872

On free line arrangements with double, triple and quadruple points

Marek Janasz·Izabela Leśniak
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Abstract

We show that there are only finitely many combinatorial types of free real line arrangements with only double, triple and quadruple intersection points, and we enlist all admissible weak-combinatorics of them. Then we classify all real $M$-line arrangements. In particular, we show that real $M$-line arrangements are simplicial.

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Marek Janasz, Izabela Leśniak. 2025-09-30. On free line arrangements with double, triple and quadruple points. https://arxiv.org/abs/2504.05872

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