TY - JOUR ID - ElAmrouss2021 LB - ElAmrouss2021 AU - El Amrouss, Abdelrachid AU - Hammouti, Omar TI - Spectrum of discrete 2n-th order difference operator with periodic boundary conditions and its applications ST - Spectrum of discrete 2n-th order difference operator with periodic boundary conditions and its applications JO - Opuscula Math. JA - Opuscula Math. JF - Opuscula Mathematica PY - 2021 VL - 41 IS - 4 SP - 489 EP - 507 DO - https://doi.org/10.7494/OpMath.2021.41.4.489 UR - https://doi.org/10.7494/OpMath.2021.41.4.489 AB - Let \(n\in\mathbb{N}^{*}\), and \(N\geq n\) be an integer. We study the spectrum of discrete linear \(2n\)-th order eigenvalue problems \[\begin{cases}\sum_{k=0}^{n}(-1)^{k}\Delta^{2k}u(t-k) = \lambda u(t) ,\quad & t\in[1, N]_{\mathbb{Z}}, \\ \Delta^{i}u(-(n-1))=\Delta^{i}u(N-(n-1)),\quad & i\in[0, 2n-1]_{\mathbb{Z}},\end{cases}\] where \(\lambda\) is a parameter. As an application of this spectrum result, we show the existence of a solution of discrete nonlinear \(2n\)-th order problems by applying the variational methods and critical point theory. KW - discrete boundary value problems KW - 2n-th order KW - variational methods KW - critical point theory SN - 1232-9274 ER -