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Analytic Continuation of Power Series by Regular Generalized Weighted Means

Published online by Cambridge University Press:  20 November 2018

Bruce L. R. Shawyer
Affiliation:
Department of MathematicsThe University of Western Ontario London, Ontario, CanadaN6A 5B7
Ludwig Tomm
Affiliation:
Universität UlmAbteilung für Mathematik IV Oberer Eselsberg D-7900 Ulm, West Germany
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Abstract

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The behaviour of summability transforms of power series outside their circles of convergence has been studied by many authors. In the case of the geometric series Luh [6] and Tomm [10] showed that there exist regular methods A which provide an analytic continuation into any given simply connected region G that contains the unit disc but not the point 1. Moreover, the Atransforms of the geometric series may be required to converge to any chosen analytic function on prescribed regions outside the unit circle. In this paper, these results are extended to power series representing other meromorphic functions. It is also shown that the summability methods involved may be chosen to be generalized weighted means previously introduced by Faulstich [1].

Keywords

Type
Research Article
Copyright
Copyright © Canadian Mathematical Society 1983

References

1. Faulstich, K., Summierbarkeit von Potenzreihen durch Riesz-Verfahren mit komplexen Erzeugendenfolgen, Mitt. Math. Sem. Giessen, Heft 139 (1979).Google Scholar
2. Israpilov, R. B., The summation of power series at isolated points outside the circle of convergence (Russian), Sakharth. SSR Mechn. Akad. Moambe 54 (1969), 15-16.Google Scholar
3. Israpilov, R. B., Sets of summability of power series by linear methods (Russian), Vestnik Moskov. Univ. Ser. I Math. Meh. 24 (1969), no. 3, 22-29.Google Scholar
4. Israpilov, R. B., The summability of power series outside the circle of convergence (Russian), Isv. Vyss. Učebn. Zaved. Matematika no. 2 (93) 1970, 19-26.Google Scholar
5. Luh, W., Approximation analytischer Funktionen durch überkonvergente Potenzreihen und deren Matrix-Transformierten, Mitt. Math. Sem. Giessen, Heft 88 (1970).Google Scholar
6. Luh, W., Über die Summierbarkeit der geometrischen Reihe, Mitt. Math. Sem. Giessen, Heft 113 (1974).Google Scholar
7. Luh, W. and Trautner, R., Summierbarkeit der geometrischen Reihe auf vorgeschriebenen Mengen, Manuscripta Mathematica 18, 317-326 (1976).Google Scholar
8. Russell, D. C., Summability of power series on continuous arcs outside the circle of convergence, Acad. Roy. Belg. Bull. CI. Sci. (5) 45 (1959), 1006-1030.Google Scholar
9. Tolba, S. E., On the summability of Taylor series at isolated points outside the circle of convergence, Nederl. Akad. Wetensch. Proc. Ser. A. 55 (1952), 380-387.Google Scholar
10. Tomm, L., Über die Summierbarkeit der geometrischen Reihe mit regulären Verfahren, dissertation (1979), Ulm Germany (FRG).Google Scholar
11. Tomm, L., A regular summability method which sums the geometric series to its proper value in the whole complex plane, to appear in Can. Math. Bull.Google Scholar
12. Tomm, L., A summability approximation theorem for Taylor series of meromorphic functions, J. reine u. angew. Math. 339 (1983), 133-146.Google Scholar
13. Vermes, P., Summability of power series in simply or multiply connected domains, Acad. Roy. Belg. Bull. CI. Sci. (5), 44 (1958), 188-198.Google Scholar
14. Vermes, P., Summability of power series at unbounded sets of isolated points, Acad. Roy. Belg. Bull. CI. Sci. (5), 44 (1958), 830-838.Google Scholar