On the proper orientation number of bipartite graphs
نویسندگان
چکیده
منابع مشابه
On the proper orientation number of bipartite graphs
An orientation of a graph G is a digraph D obtained from G by replacing each edge by exactly one of the two possible arcs with the same endvertices. For each v ∈ V (G), the indegree of v in D, denoted by d− D (v), is the number of arcs with head v in D. An orientation D of G is proper if d− D (u) 6= d− D (v), for all uv ∈ E(G). The proper orientation number of a graph G, denoted by − →χ (G), is...
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Graph orientation is a well-studied area of graph theory. A proper orientation of a graph G = (V,E) is an orientationD of E(G) such that for every two adjacent vertices v and u, d D (v) 6= d D (u) where d D (v) is the number of edges with head v in D. The proper orientation number of G is defined as −→χ (G) = min D∈Γ max v∈V (G) d D (v) where Γ is the set of proper orientations of G. We have χ(...
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ژورنال
عنوان ژورنال: Theoretical Computer Science
سال: 2015
ISSN: 0304-3975
DOI: 10.1016/j.tcs.2014.11.037