Perfection for strong edge-coloring on graphs
نویسندگان
چکیده
A strong edge-coloring of a graph is a function that assigns to each edge a color such that every two distinct edges that are adjacent or adjacent to a same edge receive different colors. The strong chromatic index χs(G) of a graph G is the minimum number of colors used in a strong edge-coloring of G. From a primal-dual point of view, there are three natural lower bounds of χs(G), that is σ(G) ≤ σ∗(G) ≤ am(G) ≤ χs(G). For any t ∈ {σ, σ∗, am}, a graph G is vertex t-perfect (respectively, edge t-perfect) if t(H) = χs(H) for any induced (respectively, edge-induced) subgraph H of G. The aim of this paper is to study the above versions of perfection on strong edge-coloring.
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