Let Isubsetmathbb{R} be an open interval with 0in I, and let gin C^{1}(I, (0,+infty)). Let Ninmathbb{N} be an integer with Ngeq4, [2, N-1]_{mathbb{Z}}:={2, 3,ldots,N-1}. We are concerned with the existence of solutions for the discrete Neumann problem \t\t\t{∇(kn−1△vk1−(△vk)2)=nkn−1[−g′(ψ−1(vk))1−(△vk)2+g(ψ−1(vk))H(ψ−1(vk),k)],k∈[2,N−1]Z,Δv1=0=ΔvN−1\\documentclass[12pt]{minimal}\t\t\t\t\\usepackage{amsmath}\t\t\t\t\\usepackage{wasysym}\t\t\t\t\\usepackage{amsfonts}\t\t\t\t\\usepackage{amssymb}\t\t\t\t\\usepackage{amsbsy}\t\t\t\t\\usepackage{mathrsfs}\t\t\t\t\\usepackage{upgreek}\t\t\t\t\\setlength{\\oddsidemargin}{-69pt}\t\t\t\t\\begin{document}$$\\textstyle\\begin{cases} \\nabla(k^{n-1}\\frac{\\triangle v_{k}}{\\sqrt{1-(\\triangle v_{k})^{2}}} )=nk^{n-1}[-\\frac{ g'(\\psi^{-1}(v_{k}))}{\\sqrt{1-(\\triangle v_{k})^{2}}}+g(\\psi^{-1}(v_{k}))H(\\psi^{-1}(v_{k}),k)],\\quad k\\in[2, N-1]_{\\mathbb{Z}},\\\\ \\Delta v_{1}=0=\\Delta v_{N-1} \\end{cases} $$\\end{document} which is a discrete analogue of the Neumann problem about the rotationally symmetric spacelike graphs with a prescribed mean curvature function in some Friedmann-Lemaître-Robertson-Walker (FLRW) spacetimes, where psi(s):=int_{0}^{s}frac{dt}{g(t)}, psi ^{-1} is the inverse function of ψ, and H:mathbb{R}times[2, N-1]_{mathbb{Z}}tomathbb{R} is continuous with respect to the first variable. The proofs of the main results are based upon the Brouwer degree theory.
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