A Fejer Riesz inequality for the weighted Besov spaces Bp,q is given. Some characteriza- tions of functions in Bp.q in terms of their Taylor coefficients are obtained.
Let K be a right-continuous and nondecreasing function. A function f analytic in the unit disk D belongs to the space OK if ∫D｜f＇（z）｜2K（1 - ｜z｜2）dA（z） 〈 ∞. Decomposition theorems for OK spaces are established in this paper. As an application, we obtain a characterization of interpolation by functions in DK spaces. Furthermore, we characterize functions in DK spaces by conjugate pairs.
