Page 1 Next

Displaying 1 – 20 of 106

Showing per page

A formula for the Bloch norm of a C 1 -function on the unit ball of n

Miroslav Pavlović (2008)

Czechoslovak Mathematical Journal

For a C 1 -function f on the unit ball 𝔹 n we define the Bloch norm by f 𝔅 = sup d ˜ f , where d ˜ f is the invariant derivative of f , and then show that f 𝔅 = sup z , w 𝔹 z w ( 1 - | z | 2 ) 1 / 2 ( 1 - | w | 2 ) 1 / 2 | f ( z ) - f ( w ) | | w - P w z - s w Q w z | .

An analogue of Montel’s theorem for some classes of rational functions

R. K. Kovacheva, Julian Lawrynowicz (2002)

Czechoslovak Mathematical Journal

For sequences of rational functions, analytic in some domain, a theorem of Montel’s type is proved. As an application, sequences of rational functions of the best L p -approximation with an unbounded number of finite poles are considered.

An extension of Schwick's theorem for normal families

Yasheng Ye, Xuecheng Pang, Liu Yang (2015)

Annales Polonici Mathematici

In this paper, the definition of the derivative of meromorphic functions is extended to holomorphic maps from a plane domain into the complex projective space. We then use it to study the normality criteria for families of holomorphic maps. The results obtained generalize and improve Schwick's theorem for normal families.

An indestructible Blaschke product in the little Bloch space.

Christopher J. Bishop (1993)

Publicacions Matemàtiques

The little Bloch space, B0, is the space of all holomorphic functions f on the unit disk such that limlzl→1 lf'(z)l (1- lzl2) = 0. Finite Blaschke products are clearly in B0, but examples of infinite products in B0 are more difficult to obtain (there are now several constructions due to Sarason, Stephenson and the author, among others). Stephenson has asked whether B0 contains an infinite, indestructible Blaschke product, i.e., a Blaschke product B so that (B(z) - a)/(1 - âB(z)), is also a Blaschke...

Bounds for the derivative of certain meromorphic functions and on meromorphic Bloch-type functions

Bappaditya Bhowmik, Sambhunath Sen (2024)

Czechoslovak Mathematical Journal

It is known that if f is holomorphic in the open unit disc 𝔻 of the complex plane and if, for some c > 0 , | f ( z ) | 1 / ( 1 - | z | 2 ) c , z 𝔻 , then | f ' ( z ) | 2 ( c + 1 ) / ( 1 - | z | 2 ) c + 1 . We consider a meromorphic analogue of this result. Furthermore, we introduce and study the class of meromorphic Bloch-type functions that possess a nonzero simple pole in 𝔻 . In particular, we obtain bounds for the modulus of the Taylor coefficients of functions in this class.

Currently displaying 1 – 20 of 106

Page 1 Next