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Zapiski Nauchnykh Seminarov POMI, 2021, Volume 503, Pages 154–171
(Mi znsl7106)
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Polynomial approximations in a convex domain in $\mathbb C^n$ with the exponential decaying inside
N. A. Shirokovab a Saint Petersburg State University
b National Research University "Higher School of Economics", St. Petersburg Branch
Abstract:
Let $\Omega$ be convex domain in $\mathbb C^n$ satisfying some restrictions, $f$ be holomorphic in $\Omega$ and continuons in $\overline{\Omega}$, $f\in H^{r+\omega}(\overline{\Omega})$ with a modulus of continuity $\omega$. Then there are polynomials $P_N$, $\deg P_N\le N$, such that $ |f(z)-P_N(z)| \le cN^{-r}\omega(\frac{1}{N})$, $z \in \overline{\Omega}$, and $|f(z)-P_N(z)| \le c \exp(-c_0(K)N)$, $z\in K\subset \Omega$, where $K$ is any compact strictly inside $\Omega$.
Key words and phrases:
polynomial approximation, convex domains in $\mathbb C^n$, holomorphic functions.
Received: 09.06.2021
Citation:
N. A. Shirokov, “Polynomial approximations in a convex domain in $\mathbb C^n$ with the exponential decaying inside”, Investigations on linear operators and function theory. Part 49, Zap. Nauchn. Sem. POMI, 503, POMI, St. Petersburg, 2021, 154–171
Linking options:
https://www.mathnet.ru/eng/znsl7106 https://www.mathnet.ru/eng/znsl/v503/p154
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Abstract page: | 94 | Full-text PDF : | 24 | References: | 19 |
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