Integrable Weak Saddles for Trigonometric Liénard Systems

  • Claudia VallsEmail author


We give a complete algebraic characterization of the integrable weak saddles for planar trigonometric Liénard systems. The main tools used in our proof are the classification of the weak saddles on planar analytic Liénard systems and the characterization of some subfields of the quotient field of the ring of trigonometric polynomials.


Weak saddle Trigonometric polynomials Liénard systems 

Mathematics Subject Classification (2010)

Primary 34A05 Secondary 34C05 37C10 


Funding Information

The study is partially supported by the Portuguese agency FCT through UID/MAT/04459/2013.


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© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Departamento de Matemática, Instituto Superior TécnicoUniversidade de LisboaLisbonPortugal

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