若一个连通图G的点集是V(G)={v1,v2,…,vn}.图G的距离矩阵D(G)=(dij),其中dij表示点vi与vj之间的距离.TrG(vi)表示点vi到图G所有其他点的距离之和,Tr(G)表示i行i列位置的元素是TrG(vi)的对角矩阵.G的距离无符号拉普拉斯矩阵QD(G)=Tr(G)+D(G).QD(G)的最大特征值λQ(G)是图G的距离无符号拉普拉斯谱半径.本文分别确定了变换为团路的团树中具有最大与最小的距离无符号拉普拉斯谱半径的极图.
Suppose that the vertex set of a connected graph G is V(G) = {v1 ,v2,…,vn} and D(G) = (dij) is the distance matrix of G, where dij/is distances between vi and vj. Then we denote the sum of distances between vi and all other vertices of G. Let Tr(G) be the n x n diagonal matrix with its (i,i) - entry equal to Trc ( vi ). Then QD (G) = Tr(G) + D(G) is the distance signless Laplacian matrix of G. The largest eigenvalues of QD( G), denoted by λQ (G) ,is distance signless Laplacian spectral radius of G. In this paper we characterize extremal graphs with the maximal and minimum distance signless Laplaeian spectral radius of transformed clique path among clique trees.