Let G be a connected graph with vertex-set V(G)and edge-set E(G).A subset F of E(G)is an s-restricted edge-cut of G if G-F is disconnected and every component of G-F has at least s vertices.Letλs(G)be the minimum siz...Let G be a connected graph with vertex-set V(G)and edge-set E(G).A subset F of E(G)is an s-restricted edge-cut of G if G-F is disconnected and every component of G-F has at least s vertices.Letλs(G)be the minimum size of all s-restricted edge-cuts of G andξs(G)=min{|[X,V(G)\X]|:|X|=s,G[X]is connected},where[X,V(G)\X]is the set of edges with exactly one end in X.A graph G with an s-restricted edge-cut is called super s-restricted edge-connected,in short super-λs,ifλs(G)=ξs(G)and every minimum s-restricted edge-cut of G isolates one component G[X]with|X|=s.It is proved in this paper that a connected vertex-transitive graph G with degree k>5 and girth g>5 is super-λs for any positive integer s with s 2g or s 10 if k=g=6.展开更多
Let G be a fc-regular connected vertex transitive graph. If G is not maximal restricted edge connected, then G has a (k- 1)-factor with components isomorphic to the same vertex transitive graph of order between k and ...Let G be a fc-regular connected vertex transitive graph. If G is not maximal restricted edge connected, then G has a (k- 1)-factor with components isomorphic to the same vertex transitive graph of order between k and 2k-3. This observation strenghen to some extent the corresponding result obtained by Watkins, which said that fc-regular vertex transitive graph G has a factor with components isomorphic to a vertex transitive graphs if G is not k connected.展开更多
基金supported by National Natural Science Foundation of China(Grant No.61073046)
文摘Let G be a connected graph with vertex-set V(G)and edge-set E(G).A subset F of E(G)is an s-restricted edge-cut of G if G-F is disconnected and every component of G-F has at least s vertices.Letλs(G)be the minimum size of all s-restricted edge-cuts of G andξs(G)=min{|[X,V(G)\X]|:|X|=s,G[X]is connected},where[X,V(G)\X]is the set of edges with exactly one end in X.A graph G with an s-restricted edge-cut is called super s-restricted edge-connected,in short super-λs,ifλs(G)=ξs(G)and every minimum s-restricted edge-cut of G isolates one component G[X]with|X|=s.It is proved in this paper that a connected vertex-transitive graph G with degree k>5 and girth g>5 is super-λs for any positive integer s with s 2g or s 10 if k=g=6.
基金Supported by NNSF of China (Grant No. 10271105) Foundation of Education Ministry of Fujian Province (Grant No. AJ03147) Foundation of Science and Technology Ministry of Fujian Province (Grant No. 2003J036)
基金Supported by NNSF of China(10271105) Doctoral Foundation of Zhangzhou Normal College.
文摘Let G be a fc-regular connected vertex transitive graph. If G is not maximal restricted edge connected, then G has a (k- 1)-factor with components isomorphic to the same vertex transitive graph of order between k and 2k-3. This observation strenghen to some extent the corresponding result obtained by Watkins, which said that fc-regular vertex transitive graph G has a factor with components isomorphic to a vertex transitive graphs if G is not k connected.
