H. Bergold

activity

20192026

most citedInvestigating Simple Drawings of

K_{n}

using SAT

1 citations · 2 across the 9 of their papers we have counts for

collaborators

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4 papers · 1 filter

math.CO2024

Signotopes with few plus signs

Helena Bergold, Lukas Egeling, Hung. P. Hoang

Arrangements of pseudohyperplanes are widely studied in computational geometry. A rich subclass of pseudohyerplane arrangements, which has gained more attention in recent years, is…

math.CO2024★ 1 cited

Subgraph-universal planar graphs for trees

Helena Bergold, Vesna Iršič, Robert Lauff +3

We show that there exists an outerplanar graph on $O (n^{c})$ vertices for $c = lo g_{2} (3 + 10) \approx 2.623$ that contains every tree on $n$ vertices as a subgraph. This exten…

math.CO2019

A Semi-strong Perfect Digraph Theorem

Stephan Dominique Andres, Helena Bergold, Winfried Hochstättler +1

Reed showed that, if two graphs are $P_{4}$ -isomorphic, then either both are perfect or none of them is. In this note we will derive an analogous result for perfect digraphs.

math.CO2019

On the Geometry of Holmsen's Combinatorial Version of the Colorful Carathéodory

Helena Bergold, Winfried Hochstättler

Carathéodorys Theorem of convex hulls plays an important role in convex geometry. In 1982, Bárány formulated and proved a more general version, called the Colorful Carathéodory. Th…