Abstract
This paper is a survey of the results obtained by the author in 1996–2004 and connected with extrapolation, extension, sharp constants in Kolmogorov-type inequalities, and related questions. For the most important theorems, the key steps in the proofs are presented, which may be of independent interest.
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Original Russian Text © G.A. Kalyabin, 2006, published in Trudy Matematicheskogo Instituta imeni V.A. Steklova, 2006, Vol. 255, pp. 161–169.
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Kalyabin, G.A. Some problems for Sobolev spaces on the half-line. Proc. Steklov Inst. Math. 255, 150–158 (2006). https://doi.org/10.1134/S0081543806040122
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DOI: https://doi.org/10.1134/S0081543806040122