Padé Approximants in Complex Points Revisited
نویسندگان
چکیده
In 1976, Chisholm et al. 1 published a paper concerning the location of poles and zeros of Padé approximants of ln 1 − z developed at the complex point ζ : ln 1 − z ln 1 − ζ − ∑∞ n 1 1/n z − ζ/1 − ζ . They claimed that all poles and zeros of diagonal Padé approximants n/n interlace on the cut z ζ t 1 − ζ , t ∈ 1,∞ . Unfortunately, this result is only partially true, for poles. Klarsfeld remarked in 1981 2 that the zeros do not follow this rule. The study of this problemwas the starting motivation of the present work.We consider the general class of complexsymmetric functions f , that is, functions satisfying the following condition:
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عنوان ژورنال:
- Int. J. Math. Mathematical Sciences
دوره 2011 شماره
صفحات -
تاریخ انتشار 2011