The boundedness of the weighted differentiation composition operator from the logarithmic Bloch space to the weighted-type space is characterized in terms of the sequence (zn)n∈N0 . An asymptotic estimate of the essential norm of the operator is also given in terms of the sequence, which gives a characterization for the compactness of the operator.

We give a new and simple compactness criterion for composition operators Cφ on BMOA and the Bloch space in terms of the norms of φ in the respective spaces.

and Applied Analysis 3 Let D be the differentiation operator on H D , that is, Df z f ′ z . For f ∈ H D , the products of composition and differentiation operators DCφ and CφD are defined, respectively, by DCφ ( f ) ( f ◦ φ)′ f ′(φ) φ′, CφD ( f ) f ′ ( φ ) , f ∈ H D . 1.8 The boundedness and compactness of DCφ on the Hardy space were investigated by Hibschweiler and Portnoy in 11 and by Ohno in...

The problem of countably quasi-barrelledness of weighted spaces of continuous functions, of which there are no results in the general setting of weighted spaces, is tackled in this paper. This leads to the study of quasi-barrelledness of weighted spaces in which, unlike that of Ernst and Schnettler (1986), though with a similar approach, we drop the assumption that the weighted space has a fund...