Abstract
In this paper we prove that the Kolmogorov widths of the weighted Sobolev class W p,g r,k [a, b] with restrictions f(a) = · · · = f(k-1)(a) = f(k)(b) = · · · = f(r-1)(b) = 0 in the weighted Lebesgue space L q,v [a, b] coincide with the spectral numbers of some nonlinear differential equation. We assume that 1 < q ≤ p < ∞, the weights are positive almost everywhere, and the Sobolev class is compactly embedded in the space L q,v [a, b].
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The research was financially supported by the Russian Foundation for Basic Research (grant no. 16-01-00295).
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Vasil’eva, A.A. Widths of weighted Sobolev classes with constraints f(a) = · · · = f(k-1)(a) = f(k)(b) = · · · = f(r-1)(b) = 0 and the spectra of nonlinear differential equations. Russ. J. Math. Phys. 24, 376–398 (2017). https://doi.org/10.1134/S1061920817030116
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DOI: https://doi.org/10.1134/S1061920817030116