A lower bound for the number of zeros of a meromorphic function and its second derivative

被引:11
作者
Langley, JK [1 ]
机构
[1] UNIV NOTTINGHAM,NOTTINGHAM NG7 2RD,ENGLAND
关键词
D O I
10.1017/S0013091500022884
中图分类号
O1 [数学];
学科分类号
0701 ; 070101 ;
摘要
We prove that for a function f(z) transcendental and meromorphic in the plane and not of the form exp(az+b), we have either N(r,1/ff'')not equal 0(T(r,f'/f)) or (r-->infinity)lim log N(r,1/ff '')/loglogr greater than or equal to 2.
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页码:171 / 185
页数:15
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