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arXiv · 1802.01831

Estimate for norm of a composition operator on the Hardy-Dirichlet space

Perumal Muthukumar·Saminathan Ponnusamy·Hervé Queffélec
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Abstract

By using the Schur test, we give some upper and lower estimates on the norm of a composition operator on $\mathcal{H}^2$, the space of Dirichlet series with square summable coefficients, for the inducing symbol $\varphi(s)=c_1+c_{q}q^{-s}$ where $q\geq 2$ is a fixed integer. We also give an estimate on the approximation numbers of such an operator.

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Perumal Muthukumar, Saminathan Ponnusamy, Hervé Queffélec. 2018-02-06. Estimate for norm of a composition operator on the Hardy-Dirichlet space. https://arxiv.org/abs/1802.01831

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