Search Results - "Wiederrecht, Sebastian"

Matching Minors in Bipartite Graphs by Wiederrecht, Sebastian

“…Matchingminoren sind eine Spezialisierung des herkömmlichen Minorenbegrifs für Graphen, die die Existenz und elementare strukturelle Eigenschaften von…”
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Digraphs of directed treewidth one by Wiederrecht, Sebastian

“…We characterise digraphs of directed treewidth one in terms of forbidden butterfly minors and in terms of the structure of the cycle hypergraph to a digraph D,…”
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Excluding a planar matching minor in bipartite graphs by Giannopoulou, Archontia C., Kreutzer, Stephan, Wiederrecht, Sebastian

“…The notion of matching minors is a specialisation of minors fit for the study of graphs with perfect matchings. Matching minors have been used to give a…”
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Matching theory and Barnette's conjecture by Gorsky, Maximilian, Steiner, Raphael, Wiederrecht, Sebastian

“…Barnette's Conjecture claims that all cubic, 3-connected, planar, bipartite graphs are Hamiltonian. We give a translation of this conjecture into the…”
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Killing a vortex by Thilikos, Dimitrios M., Wiederrecht, Sebastian

“…We provide a "vortex-free" refinement of the seminal structure theorem for K_{t} -minor free graphs by Robertson and Seymour as follows: we identify a…”
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Colouring Non-Even Digraphs by Millani, Marcelo Garlet, Steiner, Raphael, Wiederrecht, Sebastian

“…A colouring of a digraph as defined by Neumann-Lara in 1982 is a vertex-colouring such that no monochromatic directed cycles exist. The minimal number of…”
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Even circuits in oriented matroids by Heuer, Karl, Steiner, Raphael, Wiederrecht, Sebastian

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Matching Connectivity: On the Structure of Graphs with Perfect Matchings by Giannopoulou, Archontia C., Kreutzer, Stephan, Wiederrecht, Sebastian

“…We introduce the concept of matching connectivity as a notion of connectivity in graphs admitting perfect matchings. The notion relies heavily on structural…”
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A Note on Directed Treewidth by Wiederrecht, Sebastian

“…We characterise digraphs of directed treewidth one in terms of forbidden butterfly minors. Moreover, we show that there is a linear relation between the…”
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Excluding Surfaces as Minors in Graphs by Thilikos, Dimitrios M, Wiederrecht, Sebastian

“…We introduce an annotated extension of treewidth that measures the contribution of a vertex set $X$ to the treewidth of a graph $G.$ This notion provides a…”
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Structure and algorithms for graphs excluding grids with small parity breaks as odd-minors by Gollin, J. Pascal, Wiederrecht, Sebastian

“…We investigate a structural generalisation of treewidth we call $\mathcal{A}$-blind-treewidth where $\mathcal{A}$ denotes an annotated graph class. This width…”
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Approximating branchwidth on parametric extensions of planarity by Thilikos, Dimitrios M, Wiederrecht, Sebastian

“…The branchwidth of a graph has been introduced by Roberson and Seymour as a measure of the tree-decomposability of a graph, alternative to treewidth…”
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A note on the 2-Factor Hamiltonicity Conjecture by Gorsky, Maximilian, Johanni, Theresa, Wiederrecht, Sebastian

“…The 2-factor Hamiltonicity Conjecture by Funk, Jackson, Labbate, and Sheehan [JCTB, 2003] asserts that all cubic, bipartite graphs in which all 2-factors are…”
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Killing a Vortex by Thilikos, Dimitrios M, Wiederrecht, Sebastian

“…The Graph Minors Structure Theorem of Robertson and Seymour asserts that, for every graph $H,$ every $H$-minor-free graph can be obtained by clique-sums of…”
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The Strong Colors of Flowers - The Structure of Graphs with Chordal Squares by Wiederrecht, Sebastian

“…A proper vertex coloring of a graph is a mapping of its vertices on a set of colors, such that two adjacent vertices are not mapped to the same color. This…”
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A Flat Wall Theorem for Matching Minors in Bipartite Graphs by Giannopoulou, Archontia C, Wiederrecht, Sebastian

“…A major step in the graph minors theory of Robertson and Seymour is the transition from the Grid Theorem which, in some sense uniquely, describes areas of…”
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Two Disjoint Alternating Paths in Bipartite Graphs by Giannopoulou, Archontia C, Wiederrecht, Sebastian

“…A bipartite graph B is called a brace if it is connected and every matching of size at most two in B is contained in some perfect matching of B and a cycle C…”
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Obstructions to Erd\H{o}s-P\'osa Dualities for Minors by Paul, Christophe, Protopapas, Evangelos, Thilikos, Dimitrios M, Wiederrecht, Sebastian

“…Let ${\cal G}$ and ${\cal H}$ be minor-closed graph classes. The pair $({\cal H},{\cal G})$ is an Erd\H{o}s-P\'osa pair (EP-pair) if there is a function $f$…”
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Delineating Half-Integrality of the Erd\H{o}s-P\'osa Property for Minors: the Case of Surfaces by Paul, Christophe, Protopapas, Evangelos, Thilikos, Dimitrios M, Wiederrecht, Sebastian

“…In 1986 Robertson and Seymour proved a generalization of the seminal result of Erd\H{o}s and P\'osa on the duality of packing and covering cycles: A graph has…”
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Unavoidable induced subgraphs in graphs with complete bipartite induced minors by Chudnovsky, Maria, Hatzel, Meike, Korhonen, Tuukka, Trotignon, Nicolas, Wiederrecht, Sebastian

“…We prove that if a graph contains the complete bipartite graph $K_{134, 12}$ as an induced minor, then it contains a cycle of length at most~12 or a theta as…”
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