Showing items related by title, author, creator and subject.

• Centers for the Kukles homogeneous systems with even degree 

  Giné, Jaume; Llibre, Jaume; Valls, Claudia (Shanghai Normal University & Wilmington Scientific Publisher, 2017)

  For the polynomial differential system x˙=−y, y˙=x+Qn(x,y), where Qn(x,y) is a homogeneous polynomial of degree n there are the following two conjectures done in 1999. (1) Is it true that the previous system for n≥2 has a ...

• Analytic nilpotent centers as limits of nondegenerate centers revisited 

  García, I. A. (Isaac A.); Giacomini, Héctor; Giné, Jaume; Llibre, Jaume (Elsevier, 2016-04-25)

  We prove that all the nilpotent centers of planar analytic differential systems are limit of centers with purely imaginary eigenvalues, and consequently the Poincaré--Liapunov method to detect centers with purely imaginary ...

• The problem of distinguishing between a center and a focus for nilpotent and degenerate analytic systems 

  Giacomini, Héctor; Giné, Jaume; Llibre, Jaume (Elsevier, 2006)

  In this work we study the centers of planar analytic vector fields which are limit of linear type centers. It is proved that all the nilpotent centers are limit of linear type centers and consequently the Poincaré–Liapunov ...