Vol. 47, No. 2, 1973

Download this article
Download this article. For screen
For printing
Recent Issues
Vol. 332: 1  2
Vol. 331: 1  2
Vol. 330: 1  2
Vol. 329: 1  2
Vol. 328: 1  2
Vol. 327: 1  2
Vol. 326: 1  2
Vol. 325: 1  2
Online Archive
Volume:
Issue:
     
The Journal
About the journal
Ethics and policies
Peer-review process
 
Submission guidelines
Submission form
Editorial board
Officers
 
Subscriptions
 
ISSN 1945-5844 (electronic)
ISSN 0030-8730 (print)
 
Special Issues
Author index
To appear
 
Other MSP journals
The behavior of the norm of an automorphism of the unit disk

Dennis Michael Girard

Vol. 47 (1973), No. 2, 443–456
Abstract

For f(z) analytic on the closed unit disk,

      ∑
f(z) =   akzk,

let

∥f ∥ = ∑ |ak|.

In this paper the following result is obtained: Theorem. Let f(z) be an automorphism of the unit disk:

f (z) = eiζ-z −-α-,0 < |α| < 1,ζ real.
1− αz

Then

            √-
√1-∥fn∥ ∼ -82-21-(1− β2)1∕2F (1, 3; 3;1 − β2 )
n       Γ (4)            2 4 2

as n →∞ where F = 2F1 is the hypergeometric function and

   1 − |α|
β = 1-+-|α|.

Mathematical Subject Classification
Primary: 42A28
Secondary: 30A24
Milestones
Received: 8 May 1972
Revised: 2 January 1972
Published: 1 August 1973
Authors
Dennis Michael Girard