Title of article :
Restricted T-Universal Functions Original Research Article
Author/Authors :
Wolfgang Luh، نويسنده , , Valeri A. Martirosian ، نويسنده , , Jürgen Müller، نويسنده ,
Issue Information :
روزنامه با شماره پیاپی سال 2002
Abstract :
We prove the existence of a function ϕ which is holomorphic exactly in the unit disk D and has universal translates with respect to a prescribed closed set E⊂∂D and satisfies ϕ∈C∞(∂D\E). If Q is a subsequence of N0 with upper density d(Q)=1 then the function ϕ can be constructed such that in additionϕ (z)=∑n=0∞ anzn with an=0 if n∉Q.
Keywords :
* universal functions , * gap power series , * boundary behaviour of holomorphic functions , * lacunary polynomial approximation
Journal title :
Journal of Approximation Theory
Journal title :
Journal of Approximation Theory