Abstract
Let us consider on interval (0, 1) a differential pencil with three n-fold characteristic roots and decaying boundary-value conditions, only one of which is related to the end of 1. We solve problem of expanding of 3n times continuously differentiable function into a Fourier series in the root elements of the pencil. The studied problem essentially generalizes the previous considerations, which concern only the relatively simple cases of pencils with two n-fold characteristic roots. New method are used in estimating the resolvent of the problem. As for the problem under consideration with three n-fold characteristics, it dose not fit into the solution scheme of previous works and is associated with overcoming of exact constructions and calculations.
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Russian Text © The Author(s), 2019, published in Izvestiya Vysshikh Uchebnykh Zavedenii. Matematika, 2019, No. 11, pp. 10–15.
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Vagabov, A.I. Regularity of a Problem of 3n-th Order with Decaying Boundary-Value Conditions. Russ Math. 63, 7–12 (2019). https://doi.org/10.3103/S1066369X19110021
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DOI: https://doi.org/10.3103/S1066369X19110021