节点文献
单圈图的最大特征值的上界的改进(英文)
Improved Upper Bounds for the Largest Eigenvalue of Unicyclic Graphs
【摘要】 Let G(V,E) be a unicyclic graph,Cm be a cycle of length m and Cm G,and ui ∈ V(Cm).The G-E(Cm) are m trees,denoted by Ti,i = 1,2,...,m.For i = 1,2,...,m,let eui be the excentricity of ui in Ti andec = max{eui:i = 1,2,...,m}.Let k = ec+1.For j = 1,2,...,k-1,letδij = max{dv:dist(v,ui) = j,v ∈ Ti},δj = max{δij:i = 1,2,...,m},δ0 = max{dui:ui ∈ V(Cm)}.ThenIf G≌ Cn,then the equality holds,where λ1(G) is the largest eigenvalue of the adjacency matrix of G.
【Abstract】 Let G(V,E) be a unicyclic graph,Cm be a cycle of length m and Cm G,and ui ∈ V(Cm).The G-E(Cm) are m trees,denoted by Ti,i = 1,2,...,m.For i = 1,2,...,m,let eui be the excentricity of ui in Ti andec = max{eui:i = 1,2,...,m}.Let k = ec+1.For j = 1,2,...,k-1,letδij = max{dv:dist(v,ui) = j,v ∈ Ti},δj = max{δij:i = 1,2,...,m},δ0 = max{dui:ui ∈ V(Cm)}.ThenIf G≌ Cn,then the equality holds,where λ1(G) is the largest eigenvalue of the adjacency matrix of G.
【Key words】 unicyclic graph； adjacency matrix； largest eigenvalue；
- 【文献出处】 数学研究与评论 ,Journal of Mathematical Research and Exposition , 编辑部邮箱 ,2009年05期
- 【分类号】O157.5
- 【被引频次】1
- 【下载频次】45