Centers and Limit Cycles of Vector Fields Defined on Invariant Spheres
نویسندگان
چکیده
The aim of this paper is the study center-focus and cyclicity problems inside class $$\mathfrak {X}$$ 3-dimensional vector fields that admit a first integral leaves invariant any sphere centered at origin. We classify centers linear, quadratic homogeneous family $$\mathcal {F}\subset \mathfrak , restricted to one these spheres. Moreover, we show existence least 4 limit cycles in {F}$$ .
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ژورنال
عنوان ژورنال: Journal of Nonlinear Science
سال: 2021
ISSN: ['0938-8974', '1432-1467']
DOI: https://doi.org/10.1007/s00332-021-09751-z