Characterising subclasses of perfect graphs with respect to partial orders related to edge contraction
نویسندگان
چکیده
Characterising graph classes by forbidding a set of graphs has been a common feature in graph theory for many years. Up to date many classes have been char-acterised with respect to the induced subgraph relation and there are a plethora of results regarding graph classes closed under the minor relation. We consider the characterisation of graph classes closed under partial orders including edge contraction as an operation. More concretely we consider contraction minors and a newly defined partial order, under which many of the graph classes considered here can be characterised by a finite minimal forbidden set.
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