Bifurcation of limit cycles and integrability conditions for 6-parameter families of polynomial vector fields of arbitrary degree

General center conditions and bifurcatio

General center conditions and bifurcation of limit cycles for a quasi-symmetric seventh degree system

✍ Chaoxiong Du; Yirong Liu 📂 Article 📅 2008 🏛 Elsevier Science 🌐 English ⚖ 770 KB

In this paper, we study a class of quasi-symmetric seventh degree system. By making two appropriate transformations of system (3) and calculating general focal values carefully, we obtain the conditions that the infinity and the elementary focus (-1 2 , 0) become centers at the same time. Moreover,