Convexity in graphs
نویسندگان
چکیده
منابع مشابه
Convexity Notions in Graphs
Let V be a finite set andM a finite collection of subsets of V . ThenM is an alignment of V if and only if M is closed under taking intersections and contains both V and the empty set. If M is an alignment of V , then the elements of M are called convex sets and the pair (V,M) is called an aligned space or a convexity space. If S ⊆ V , then the convex hull of S, denoted by CH(S), is the smalles...
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Let D be a connected oriented graph. A set S ⊆ V (D) is convex in D if, for every pair of vertices x, y ∈ S, the vertex set of every x− y geodesic (x− y shortest dipath) and y−x geodesic in D is contained in S. The convexity number con(D) of a nontrivial oriented graph D is the maximum cardinality of a proper convex set of D. Let G be a graph and SC(G) = {con(D) : D is an orientation of G} and ...
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ژورنال
عنوان ژورنال: Journal of Differential Geometry
سال: 1981
ISSN: 0022-040X
DOI: 10.4310/jdg/1214436096