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Qualitative Theory of Dynamical Systems

, Volume 9, Issue 1–2, pp 319–324 | Cite as

Focal Values of Plane Cubic Centers

  • Hans-Christian Graf v. BothmerEmail author
  • Jakob Kröker
Open Access
Article

Abstract

We prove that the vanishing of 11 focal values is not sufficient to ensure that a complex plane cubic system has a complex center. This is done by finding a complex cubic system with a high order weak focus using an extensive computer search.

Keywords

Tangent Space Formal Power Series Rational Polynomial Weighted Degree Convergent Power Series 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Notes

Open Access

This article is distributed under the terms of the Creative Commons Attribution Noncommercial License which permits any noncommercial use, distribution, and reproduction in any medium, provided the original author(s) and source are credited.

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Copyright information

© The Author(s) 2010

Authors and Affiliations

  1. 1.Courant Research Centre “Higher Order Structures”, Mathematisches InstitiutGeorg-August-Universität GöttingenGöttingenGermany

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