Reachability relations in digraphs
نویسندگان
چکیده
منابع مشابه
Reachability Relations and the Structure of Transitive Digraphs
In this paper we investigate reachability relations on the vertices of digraphs. If W is a walk in a digraph D, then the height of W is equal to the number of edges traversed in the direction coinciding with their orientation, minus the number of edges traversed opposite to their orientation. Two vertices u, v ∈ V (D) are Ra,b-related if there exists a walk of height 0 between u and v such that...
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ژورنال
عنوان ژورنال: European Journal of Combinatorics
سال: 2008
ISSN: 0195-6698
DOI: 10.1016/j.ejc.2007.11.003