Analytic functions and function spaces are fundamental concepts in complex analysis and functional analysis. Analytic functions are those that are locally represented by power series, and they play a ...

Earlier D.Đ. Tošić obtained an infinite series representation for the central difference operator ${\delta _\theta }f\left( z \right) = f\left( {z' + \frac{1}{2}h ...

For a rational matrix function Φ with poles outside the unit circle, we estimate the degree of the unique superoptimal approximation 𝒜Φ by matrix functions analytic in the unit disk. We obtain sharp ...