On the Number of Periodic Orbits to Odd Order Differential Delay Systems

oleh: Weigao Ge, Lin Li

Format: Article
Diterbitkan: MDPI AG 2020-10-01

Deskripsi

In this paper, we study the periodic orbits of a type of odd order differential delay system with <inline-formula><math display="inline"><semantics><mrow><mn>2</mn><mi>k</mi><mo>−</mo><mn>1</mn></mrow></semantics></math></inline-formula> lags via the <inline-formula><math display="inline"><semantics><msup><mi>S</mi><mn>1</mn></msup></semantics></math></inline-formula> index theory and the variational method. This type of system has not been studied by others. Our results provide a new and more accurate method for counting the number of periodic orbits.