摘要
引入了C(l,k)图类的概念:对于整数k≥0及整数l>0,用C(l,k)表示一类n阶2-边连通图.图G∈C(l,k)当且仅当对于任意的边割集SE(G),|S|≤3,使G-S的任一分支至少有(n-k)/l个顶点.证明了:若无三角形的图G∈C(6,5),则G是超欧拉的当且仅当G不能收缩为几个特殊的图.
Graph G is supereulerian, if G has a spanning eulerian subgraph. Let l〉 0 and k ≥0 be two integers. Graph G ∈C(l, k) if and only if G with order n is 2-edge-connected and for every bond S ∩→ E(G) with | S | 3, each component of G-S has order at least (n-k)/l. It is proved that ifG G∈(6, 5) and Gis triangle-free, then G is supereulerian if and only if G can not be contracted to some well classified special graphs.
出处
《西南大学学报(自然科学版)》
CAS
CSCD
北大核心
2008年第12期9-12,共4页
Journal of Southwest University(Natural Science Edition)
基金
重庆市自然科学基金资助项目(CSTC
2007BA2024)
重庆市教委资助项目(KJ0707010)
关键词
超欧拉图
可折叠子图
无三角形
简化图
supereulerian graphs
collapsible graphs
triangle-free
reduction