Structure and Coloring of (P3 ∪ P2)-free Graphs Sparse Triangles
摘要
Let G be a graph. The distance between two vertices u, v ∈ V (G) is the length of the shortest path between them, denoted by dG(u, v). For two subgraphs H and F of G, we define dG(H, F) = min{dG(u, v) : u ∈ V (H) and v ∈ V (F)} as the distance between them. In this paper, we prove that if G is (P3 ∪ P2)-free and the distance of any two triangles of G is at least 1, then χ(G) ≤ 4 (this generalizes some results of Wang and Zhang), and we draw all such G′s when ω(G) = 3 and χ(G) = 4.