A note on arc-disjoint cycles in tournaments
Tom 136 / 2014
                    
                    
                        Colloquium Mathematicum 136 (2014), 259-262                    
                                        
                        MSC: 05C20, 05C35, 05C38.                    
                                        
                        DOI: 10.4064/cm136-2-7                    
                                    
                                                Streszczenie
We prove that every vertex $v$ of a tournament $T$ belongs to at least $$\max\{\min\{\delta ^+(T), 2\delta ^+(T) - d^+_T(v) +1\}, \min\{\delta ^-(T), 2\delta ^-(T) - d^-_T(v) +1\}\}$$ arc-disjoint cycles, where $\delta ^+(T)$ (or $\delta ^-(T)$) is the minimum out-degree (resp. minimum in-degree) of $T$, and $d^+_T(v)$ (or $d^-_T(v)$) is the out-degree (resp. in-degree) of $v$.
 
             
                                                             
                                                             
                                                             
                                                             
                                                             
                                                             
                                                         
                                                            