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arXiv · 2504.11738

Infinitely many solutions for an instantaneous and non-instantaneous fourth-order differential system with local assumptions

Lijuan Kang·Xingyong Zhang·Cuiling Liu
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Abstract

We investigate a class of fourth-order differential systems with instantaneous and non-instantaneous impulses. Our technical approach is mainly based on a variant of Clark's theorem without the global assumptions. Under locally subquadratic growth conditions imposed on the nonlinear terms $f_i(t,u)$ and impulsive terms $I_i$, combined with perturbations governed by arbitrary continuous functions of small coefficient $\varepsilon$, we establish the existence of multiple small solutions. Specifically, the system exhibits infinitely many solutions in the case where $\varepsilon=0$.

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Lijuan Kang, Xingyong Zhang, Cuiling Liu. 2025-04-16. Infinitely many solutions for an instantaneous and non-instantaneous fourth-order differential system with local assumptions. https://arxiv.org/abs/2504.11738

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