图的度和与扩圈
Extending Cycles and Degree Sums in Graphs
                  
              
    
                  
                    
                    摘要: 本文讨论了两顶点的度和与圈可扩之间的关系,得到了如下结果:设图G的阶 ,如果G中任意一对不相邻的顶点u,v满足 ,则G中任意一个满足 的圈C是可扩的。这里圈C的下界是最好可能的。由此进一步得到,如果G中任意一对不相邻的顶点u,v满足 ,则G是完全圈可扩的。
                
 
              
                
                    Abstract: 
In this paper, we study the relations between degree sums and extending cycles in graphs. The following results is proved. Let G be a graph of order . If for each pair of nonadjacent vertices u,v in , then every cycle C of G with is extendable. By the result,we have that if for each pair of nonadjacent vertices u,v in , then G is fully cycle ex-tendable.
                
                   
                  
    
  
 
     
    
    
                
         
                
                
                 
                
                    
                        参考文献
                        
                            
                                    
                                        | 
                                            [1]
                                         | 
                                        
                                             J. A. Bondy,U. S. R. Murty. Graph theory with applications. New York: Macmillan London and Elsevier, 1976. 
                                         | 
                                    
                     
                                
                                    
                                        | 
                                            [2]
                                         | 
                                        
                                             G.A. Dirac. Some theorems on abstract graphs. Proceedings London Mathematical Society, 1952, s3-2(1): 69-81. 
                                         | 
                                    
                     
                                
                                    
                                        | 
                                            [3]
                                         | 
                                        
                                             O. Ore. Note on Hamilton circuits. The American Mathematical Monthly, 1960, 67: 55. 
                                         | 
                                    
                     
                                
                                    
                                        | 
                                            [4]
                                         | 
                                        
                                             G. R. T. Hendry. Extending cycles in graphs. Discrete Mathematics, 1990, 85(1): 59-72. 
                                         |