### AIMS Mathematics

2021, Issue 7: 6815-6832. doi: 10.3934/math.2021399
Research article

# Multiple periodic solutions of differential delay systems with $2k$ lags

• Received: 15 December 2020 Accepted: 14 April 2021 Published: 21 April 2021
• MSC : 34A34, 34K13

• The quantity of $2(2k+1)$-periodic solutions to a specific differential delay system with $2k$ lags is studied and resolved by variational methods. Several results are revealed and two examples are given to illustrate the application of the main results.

Citation: Li Zhang, Huihui Pang, Weigao Ge. Multiple periodic solutions of differential delay systems with $2k$ lags[J]. AIMS Mathematics, 2021, 6(7): 6815-6832. doi: 10.3934/math.2021399

### Related Papers:

• The quantity of $2(2k+1)$-periodic solutions to a specific differential delay system with $2k$ lags is studied and resolved by variational methods. Several results are revealed and two examples are given to illustrate the application of the main results.

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