Abstract
Some identities are established for reproducing kernels and extremal functions in Dirichlet-type spaces. In certain cases, these identities are characteristic. A new proof of Aleman's theorem on extremal functions as contractive multipliers is obtained. In contrast to the original one, this proof can be extended to vector-valued spaces. Bibliography: 11 titles.
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Shimorin, S.M. Reproducing Kernels and Extremal Functions in Dirichlet-Type Spaces. Journal of Mathematical Sciences 107, 4108–4124 (2001). https://doi.org/10.1023/A:1012453003423
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DOI: https://doi.org/10.1023/A:1012453003423