Perfectly contractile graphs
نویسندگان
چکیده
منابع مشابه
Algorithms for perfectly contractile graphs
We consider the class A of graphs that contain no odd hole, no antihole of length at least 5, and no “prism” (a graph consisting of two disjoint triangles with three disjoint paths between them) and the class A′ of graphs that contain no odd hole, no antihole of length at least 5, and no odd prism (prism whose three paths are odd). These two classes were introduced by Everett and Reed and are r...
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Irena Rusu Universit e d'Orl eans, L.I.F.O., B.P. 6759, 45067 Orl eans Cedex 2, France Abstract Everett et al. [2] conjectured that a graph with no odd hole and no stretcher is perfectly contractile, i.e. it can be reduced to a clique by successively contracting even pairs. We show that this conjecture is true for diamond-free graphs, and propose a polynomial algorithm to perform the successive...
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We consider the class A of graphs that contain no odd hole, no antihole, and no “prism” (a graph consisting of two disjoint triangles with three disjoint paths between them). We prove that every graph G ∈ A different from a clique has an “even pair” (two vertices that are not joined by a chordless path of odd length), as conjectured by Everett and Reed [see the chapter “Even pairs” in the book ...
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ژورنال
عنوان ژورنال: Journal of Combinatorial Theory, Series B
سال: 1990
ISSN: 0095-8956
DOI: 10.1016/0095-8956(90)90077-d