A k-adjacent strong edge coloring of graph G(V, E) is defined as a proper k-edge coloring f of graph G(V, E) such that f[u] ≠ f[v] for every uv ∈ E(G), where f[u] = {f(uw)|uw ∈ E(G)} and f(uw) denotes the color of ...A k-adjacent strong edge coloring of graph G(V, E) is defined as a proper k-edge coloring f of graph G(V, E) such that f[u] ≠ f[v] for every uv ∈ E(G), where f[u] = {f(uw)|uw ∈ E(G)} and f(uw) denotes the color of uw, and the adjacent strong edge chromatic number is defined as x'as(G) = min{k| there is a k-adjacent strong edge coloring of G}. In this paper, it has been proved that △ ≤ x'as(G) ≤ △ + 1 for outer plane graphs with △(G) ≥ 5, and X'as(G) = △ + 1 if and only if there exist adjacent vertices with maximum degree.展开更多
Using the linear space over the binary field that related to a graph G, a sufficient and necessary condition for the chromatic number of G is obtained.
基金National Natural Science Foundation of China (No. 19871036) Qinglan talent Funds of Lanzhou Jiaotong University.
文摘A k-adjacent strong edge coloring of graph G(V, E) is defined as a proper k-edge coloring f of graph G(V, E) such that f[u] ≠ f[v] for every uv ∈ E(G), where f[u] = {f(uw)|uw ∈ E(G)} and f(uw) denotes the color of uw, and the adjacent strong edge chromatic number is defined as x'as(G) = min{k| there is a k-adjacent strong edge coloring of G}. In this paper, it has been proved that △ ≤ x'as(G) ≤ △ + 1 for outer plane graphs with △(G) ≥ 5, and X'as(G) = △ + 1 if and only if there exist adjacent vertices with maximum degree.
文摘Using the linear space over the binary field that related to a graph G, a sufficient and necessary condition for the chromatic number of G is obtained.