摘要
对一个n阶连通图G,G的Hamiltonian着色(以下简称G的H着色)定义为从G的顶点集V(G)到正整数集N(称为颜色集)的一个映射c,且对G的任意2个不同顶点u和v,满足|c(u)-c(v)|+D(u,v)≥n-1,其中D(u,v)表示G中u到v的最长路径的长度。对G的一个H着色c,将Max{c(u)|u∈V(G)}称为c的值,记作hc(c)。将Min{hc(c)|c是G的H着色}称为G的Hamiltonian色数(以下简称G的H色数),记作hc(G)。如果G的一个H着色c满足hc(c)=hc(G),则称c为G的一个最小H着色。本次研究得到了完全正则m-元树的H色数的确切值,并给出了其最小H着色。
For a connected graph of G order n, a Hamiltonian coloring of G(named a H coloring of G for short) is a mapping c from a set of vertices of G to a set of positive integers V(G)→{1,2,3,…}(called a color set). And for every two distinct vertices u and v of G, the formula |c(u)-c(v)|+D(u,v)≥n-1 will be satisfied, in whih D(u,v) is the length of a longest u-v path in G. The Hamiltonian chromatic number hc(G) of G(named the H chromatic number hc(G) of G for short) is Min{hc(c)} taken over all H coloring c of G. A H coloring c of G is a minimum H coloring if hc(c)=hc(G). The exact values of H chromatic number for the completely regular m-ary trees are obtained, and a minimum H coloring for them is presented.
引文
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