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Division by Flat Ultradifferentiable Functions and Sectorial Extensions

Vincent Thilliez
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Abstract

We consider classes $ \mathcal{A}_M(S) $ of functions holomorphic in an open plane sector $ S $ and belonging to a strongly non-quasianalytic class on the closure of $ S $. In $ \mathcal{A}_M(S) $, we construct functions which are flat at the vertex of $ S $ with a sharp rate of vanishing. This allows us to obtain a Borel-Ritt type theorem for $ \mathcal{A}_M(S) $ extending previous results by Schmets and Valdivia. We also derive a division property for ideals of flat ultradifferentiable functions, in the spirit of a classical $ C^\infty $ result of Tougeron.

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Vincent Thilliez. 2006-02-17. Division by Flat Ultradifferentiable Functions and Sectorial Extensions. https://doi.org/10.1007/s00025-003-0081-1

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