Abstract
Asymptotic formulas for the fundamental solution system as \(x\to\infty\) are obtained for equations of the form
where \(p\) is a locally integrable function admitting the representation
and \(q\) is a distribution representable for some given \(k\), \(0\le k\le n\), as \(q=\sigma^{(k)}\), where
Similar results are obtained for the equations \(l(y)=\lambda y\) whose coefficients \(p(x)\) and \(q(x)\) admit the following representation for a given \(k\), \(0\le k\le n\):
where the functions \(r\) and \(s\) satisfy certain integral decay conditions. We also obtain theorems on the deficiency indices of the minimal symmetric operator generated by the differential expression \(l(y)\) (with real functions \(p\) and \(q\)) as well as theorems on the spectra of the corresponding self-adjoint extensions.
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Funding
This work was supported by the Russian Science Foundation under grant no. 20-11-20261.
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Translated from Matematicheskie Zametki, 2023, Vol. 113, pp. 217–235 https://doi.org/10.4213/mzm13882.
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Konechnaja, N.N., Mirzoev, K.A. & Shkalikov, A.A. Asymptotics of Solutions of Two-Term Differential Equations. Math Notes 113, 228–242 (2023). https://doi.org/10.1134/S0001434623010261
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DOI: https://doi.org/10.1134/S0001434623010261