International Journal of Mathematics and Mathematical Sciences
Volume 5 (1982), Issue 4, Pages 691-706
doi:10.1155/S0161171282000635
A Polya "shire" theorem for functions with algebraic singularities
J.K. Shaw
and C.L. Prather
Department of Mathematics, Virginia Polytechnic Institute and State University, Blacksburg 24061-4097, Virginia, USA
Abstract
The classical shire theorem of Pólya is proved for functions with algebraic poles, in the sense of L. V. Ahlfors. A function f(z) is said to have an algebraic pole at z0 provided there is a representation f(z)=∑k=−N∞ak(z−z0)k/p+A(z), where p and N are positive integers and A(z) is analytic at z0. For p=1, the proof given reduces to an entirely new proof of the shire theorem. New quantitative results are given on how zeros of the successive derivatives migrate to the final set.