排序方式: 共有45条查询结果,搜索用时 93 毫秒
1.
A weighting of the edges of a hypergraph is called vertex‐coloring if the weighted degrees of the vertices yield a proper coloring of the graph, i.e. every edge contains at least two vertices with different weighted degrees. In this article, we show that such a weighting is possible from the weight set for all hypergraphs with maximum edge size and not containing edges solely consisting of identical vertices. The number is best possible for this statement. 相似文献
2.
The existence problem of a ‐cycle frame of type is now solved for any quadruple . 相似文献
3.
证明了风车图K4n3(n∈自然数)及其它几类强协调图,并给出了统一的强协调值标号,最后证明了Kn-e(n≥6)是非强协调图. 相似文献
4.
5.
设G是一个简单图,在G上当且仅当两个顶点的距离为2时增加一条边,所得的图称为G的平方,记作G2;在G上每个顶点都增加一条悬挂边所得的图称为G的冠,记作I(G).设Pn是n个顶点的路,本文给出了I(Pn2)、I(Fn)、F2n徊和I(Fn2)的序列标号. 相似文献
6.
图的强协调方程及其应用 总被引:7,自引:0,他引:7
柳柏濂 《新疆大学学报(理工版)》1988,(1)
本文引进图的强协调方程的新概念,并且得出图的强协调的某些必要条件。运用上述方程,我们可以一般地研究图的强调协性质。 相似文献
7.
We study backbone colorings, a variation on classical vertex colorings: Given a graph G and a subgraph H of G (the backbone of G), a backbone coloring for G and H is a proper vertex k-coloring of G in which the colors assigned to adjacent vertices in H differ by at least 2. The minimal k∈N for which such a coloring exists is called the backbone chromatic number of G. We show that for a graph G of maximum degree Δ where the backbone graph is a d-degenerated subgraph of G, the backbone chromatic number is at most Δ+d+1 and moreover, in the case when the backbone graph being a matching we prove that the backbone chromatic number is at most Δ+1. We also present examples where these bounds are attained.Finally, the asymptotic behavior of the backbone chromatic number is studied regarding the degrees of G and H. We prove for any sparse graph G that if the maximum degree of a backbone graph is small compared to the maximum degree of G, then the backbone chromatic number is at most . 相似文献
8.
Small world effects in the harmonious unifying hybrid preferential model (HUHPM) networks are studied both numerically and analytically. The idea and method of the HUHPM is applied to three typical examples of unweighted BA model, weighted BBV model, and the TDE model, so-called HUHPM-BA, HUHPM-BBV and HUHPM-TDE networks. Comparing the HUHPM with current typical models above, it is found that the HUHPM networks has the smallest average path length and the biggest average clustering coefficient. The results demonstrate that the HUHPM is more suitable not only for the un-weighted models but also for the weighted models. 相似文献
9.
10.
An edge coloring totalk-labeling is a labeling of the vertices and the edges of a graph G with labels{1,2,...,k}such that the weights of the edges defne a proper edge coloring of G.Here the weight of an edge is the sum of its label and the labels of its two end vertices.This concept was introduce by Brandt et al.They defnedχt(G)to be the smallest integer k for which G has an edge coloring total k-labeling and proposed a question:Is there a constant K withχt(G)≤Δ(G)+12+K for all graphs G of maximum degreeΔ(G)?In this paper,we give a positive answer for outerplanar graphs by showing thatχt(G)≤Δ(G)+12+1 for each outerplanar graph G with maximum degreeΔ(G). 相似文献