On the tree-width of even-hole-free graphs
نویسندگان
چکیده
The class of all even-hole-free graphs has unbounded tree-width, as it contains complete graphs. Recently, a (even-hole, K4)-free was constructed, that still tree-width (Sintiari and Trotignon, 2019). degree arbitrarily large clique-minors. We ask whether this is necessary. prove for every graph G, if G excludes fixed H minor, then either small or wall the line induced subgraph. This can be seen strengthening Robertson Seymour’s excluded grid theorem case minor-free Our implies excluding minor bounded tree-width. In fact, our applies to more general class: (theta, prism)-free known result planar even hole-free have (Silva et al., 2010). conjecture If true, would mean even-hole-freeness testable in bounded-degree model property testing. subcubic we give bound on (even hole, pyramid)-free at most 4.
منابع مشابه
On rank-width of even-hole-free graphs
Isolde Adler Ngoc Khang Le Haiko Müller Marko Radovanović Nicolas Trotignon Kristina Vušković 1 School of Computing, University of Leeds, United Kingdom 2 CNRS, ENS de Lyon, LIP, France 3 Université de Lyon, France 4 Faculty of Mathematics, University of Belgrade, Serbia 5 Faculty of Computer Science (RAF), Union University, Serbia received 5thDec. 2016, revised 1stAug. 2017, accepted 3rdAug. 2...
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ژورنال
عنوان ژورنال: European Journal of Combinatorics
سال: 2021
ISSN: ['1095-9971', '0195-6698']
DOI: https://doi.org/10.1016/j.ejc.2021.103394