Functions with Average and Bounded Motions of a Forced Discontinuous Oscillator

  • Ricardo Enguiça
  • Rafael OrtegaEmail author


In this paper we prove the existence of bounded solutions in the real line for the equation \(\ddot{u} + \mathrm{sign}(u)=p(t)\), where p is a function with average. Some useful density results for the space of functions with zero average are also obtained.


Forced oscillator Landesman–Lazer condition Generating functions Twist maps Functions with average 


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Copyright information

© Springer Science+Business Media New York 2017

Authors and Affiliations

  1. 1.Área Departamental de MatemáticaInstituto Superior de Engenharia de LisboaLisboaPortugal
  2. 2.Departamento de Matemática AplicadaUniversidad de GranadaGranadaSpain

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