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20102026
most citedLower bounds for approximation schemes for Closest String

16 citations · 188 across the 122 of their papers we have counts for

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28 papers · 1 filter

math.CO2026

Fatness and Flatness

Arnold Filtser, Hung Le, Nikolas Mählmann +2

Fat minors are the metric analog of graph minors that are tailored to the analysis of metric (edge-weighted) graphs and, more generally, metric spaces having a suitable notion of s…

math.CO2026

A coarse block-cut tree theorem

Júlia Baligács, Václav Blažej, Jadwiga Czyżewska +2

We prove a coarse analogue of the classic fact that every graph can be decomposed along its cut-vertices into -connected components. Precisely, we prove that for every graph …

math.CO2026

A coarse Menger's Theorem for planar and bounded genus graphs

Václav Blažej, Michał Pilipczuk, Evangelos Protopapas

Menger's Theorem is a fundamental result in graph theory. It states that if in a graph with distinguished sets of terminal vertices and there are no pairwise vertex…

math.CO2026

Coarse Balanced Separators in Fat-Minor-Free Graphs

Édouard Bonnet, Hung Le, Marcin Pilipczuk +1

Fat minors are a coarse analogue of graph minors where the subgraphs modeling vertices and edges of the embedded graph are required to be distant from each other, instead of just b…

math.CO2026

Tree decompositions whose trees are subgraphs: An application of Simon's factorization

Romain Bourneuf, Gwenaël Joret, Piotr Micek +2

We show that every connected graph has a tree decomposition indexed by a tree such that is a subgraph of and the width of the tree decomposition is bounded from abo…

math.CO2026

Variants of Merge-Width and Applications

Karolina Drabik, Maël Dumas, Colin Geniet +3

Merge-width is a recently introduced family of graph parameters that unifies treewidth, clique-width, twin-width, and generalised colouring numbers. We prove the equivalence of sev…

math.CO2025

Strong odd colorings in graph classes of bounded expansion

Michał Pilipczuk

We prove that for every and a graph class of bounded expansion , there exists some so that every graph from admits a…

math.CO2025

Separability Properties of Monadically Dependent Graph Classes

Édouard Bonnet, Samuel Braunfeld, Ioannis Eleftheriadis +5

A graph class is monadically dependent if one cannot interpret all graphs in colored graphs from using a fixed first-order interpretation. We prove that m…

math.CO2025

On graphs coverable by chubby shortest paths

Meike Hatzel, Michał Pilipczuk

Dumas, Foucaud, Perez, and Todinca [SIAM J. Disc. Math., 2024] proved that if the vertex set of a graph can be covered by shortest paths, then the pathwidth of is bound…

math.CO2025

On coarse tree decompositions and coarse balanced separators

Tara Abrishami, Jadwiga Czyżewska, Kacper Kluk +3

It is known that there is a linear dependence between the treewidth of a graph and its balanced separator number: the smallest integer such that for every weighing of the verti…

math.CO2025

Obstructions and dualities for matroid depth parameters

Jakub Gajarský, Kristýna Pekárková, Michał Pilipczuk

Contraction-depth is considered to be one of the analogues of graph tree-depth in the matroid setting. In this paper, we investigate structural properties of contraction-de…

math.CO2025★ 2 cited

Graph classes through the lens of logic

Michał Pilipczuk

Graph transformations definable in logic can be described using the notion of transductions. By understanding transductions as a basic embedding mechanism, which captures the possi…

math.CO2024

Erdős-Pósa property of tripods in directed graphs

Marcin Briański, Meike Hatzel, Karolina Okrasa +1

Let be a directed graphs with distinguished sets of sources and sinks . A tripod in is a subgraph consisting of the union of two --…

math.CO2024

Half-integral Erdős-Pósa property for non-null - paths

Vera Chekan, Colin Geniet, Meike Hatzel +4

For a group , a -labelled graph is an undirected graph where every orientation of an edge is assigned an element of so that opposite orientations of the same edge are…

math.CO2023

Cliquewidth and dimension

Gwenaël Joret, Piotr Micek, Michał Pilipczuk +1

We prove that every poset with bounded cliquewidth and with sufficiently large dimension contains the standard example of dimension as a subposet. This applies in particular to…

math.CO2023★ 1 cited

Prime and polynomial distances in colourings of the plane

James Davies, Rose McCarty, Michał Pilipczuk

We give two extensions of the recent theorem of the first author that the odd distance graph has unbounded chromatic number. The first is that for any non-constant polynomial w…

math.CO2023

Partitioning edges of a planar graph into linear forests and a matching

Marthe Bonamy, Jadwiga Czyżewska, Łukasz Kowalik +1

We show that the edges of any planar graph of maximum degree at most can be partitioned into linear forests and a matching. Combined with known results, this implies that t…

math.CO2022

On digraphs without onion star immersions

Łukasz Bożyk, Oscar Defrain, Karolina Okrasa +1

The -onion star is the digraph obtained from a star with leaves by replacing every edge by a triple of arcs, where in triples we orient two arcs away from the center, a…

math.CO2022

Highly unbreakable graph with a fixed excluded minor are almost rigid

Daniel Lokshtanov, Marcin Pilipczuk, Michał Pilipczuk +1

A set in a graph is -unbreakable if every separation of order at most in satisfies or . In this…

math.CO2022

Independence number of intersection graphs of axis-parallel segments

Marco Caoduro, Jana Cslovjecsek, Michał Pilipczuk +1

We prove that for any triangle-free intersection graph of axis-parallel segments in the plane, the independence number of this graph is at least . W…

math.CO2022★ 1 cited

Transducing paths in graph classes with unbounded shrubdepth

Michał Pilipczuk, Patrice Ossona de Mendez, Sebastian Siebertz

Transductions are a general formalism for expressing transformations of graphs (and more generally, of relational structures) in logic. We prove that a graph class ca…

math.CO2022★ 1 cited

Graphs of bounded twin-width are quasi-polynomially -bounded

Michał Pilipczuk, Marek Sokołowski

We prove that for every there is a constant such that every graph with twin-width at most and clique number has chromatic number bounded by $2^{γ_t…

math.CO2022★ 1 cited

Bounding generalized coloring numbers of planar graphs using coin models

Jesper Nederlof, Michał Pilipczuk, Karol Węgrzycki

We study Koebe orderings of planar graphs: vertex orderings obtained by modelling the graph as the intersection graph of pairwise internally-disjoint discs in the plane, and orderi…

math.CO2021

On objects dual to tree-cut decompositions

Łukasz Bożyk, Oscar Defrain, Karolina Okrasa +1

Tree-cut width is a graph parameter introduced by Wollan that is an analogue of treewidth for the immersion order on graphs in the following sense: the tree-cut width of a graph is…