安新慧, 黄琼湘, 刘晓平. 关于中间图补图的一个定理的简单证明(英文)[J]. Journal of Xinjiang University (Natural Science Edition in Chinese and English), 2008, 110(2): 127-130.DOI:
关于中间图补图的一个定理的简单证明(英文)
摘要
对于图G
定义它的中间图M(G)的顶点集为V(G)∪ E(G)
顶点集中的两点x和y在M(G)中相邻当且仅当{x
y}∪ E(G)≠
并且x和y在G中相邻或者关联.在这篇文章中简化了下面这个最近已经得到的定理的证明
即一个图G的中间图M(G)的补图是哈密顿的当且仅当G不是星图
并且G不同构于{K1
2K1
K2
K2∪ K1
K3
K3∪ K1}中的任意一个图.
Abstract
For a graph G
the middle graph M(G) of G is the graph with vertex set V(G)∪E(G) in which the vertices x and y are joined by an edge if {x
y}∪E(G)≠ф
and x and y are adjacent or incident in G.In this note
we provide a simple proof for a theorem
recently obtained by An and Wu
which says that the complement of middle graph M(G) of a graph G is hamiltonian if and only if G is not a star and is not isomorphic to any graph in {K1
2K1
K2
K2∪K1
K3
K3∪K1}.
关键词
Keywords
references
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