On graphs with no induced five?vertex path or paraglider
نویسندگان
چکیده
Given two graphs H 1 and 2 , a graph is ( ) -free if it contains no induced subgraph isomorphic to or . For positive integer t, P t the chordless path on vertices. A paraglider that consists of chorless cycle C 4 plus vertex adjacent three vertices In this paper, we study structure 5 paraglider)-free graphs, show every such G satisfies ? ? ? 3 ? ? where are chromatic number clique G, respectively. Our bound attained by complement Clebsch 16 More strongly, completely characterize all > We also construct an infinite family in has = ? This shows our upper optimal up additive constant there ? -approximation algorithm for any 0.
منابع مشابه
Graphs with no induced five-vertex path or antipath
We prove that a graph G contains no induced 5-vertex path and no induced complement of a 5-vertex path if and only if G is obtained from 5-cycles and split graphs by repeatedly applying the following operations: substitution, split unification, and split unification in the complement, where split unification is a new class-preserving operation introduced here. ∗Princeton University, Princeton, ...
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ژورنال
عنوان ژورنال: Journal of Graph Theory
سال: 2021
ISSN: ['0364-9024', '1097-0118']
DOI: https://doi.org/10.1002/jgt.22656