Several equivalent conditions for the boundedness and compactness of the difference Cφ-Cψ:Zα→ Bβ were presented for α>1,β>0.As a nontrivial extension,Taylor series and Raabe discriminant are used to establish the complete characteri-zations for bounded or compact Cφ-Cψ:Zα,0→B0β.
关键词
差分/复合算子/Zygmund型空间/Bloch型空间
Key words
differences/composition operator/Zygmund-type space/Bloch-type space