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题 目：The center of planar quasi-homogeneous polynomial differential systems

时 间：5月8日（周五）上午  10:10

地 点: 理科楼202

摘 要：

We characterize the centers of the quasi-homogeneous but non-homogeneous planar polynomial differential systems of any degree $k\in N$. We prove that the system does not admit centers if $k$ is even, and present the sufficient and necessary conditions that the system admits a center if $k$ is odd. Furthermore, we provide an algorithm to obtain the system which has a center.