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arXiv · 2606.02968

A ribbon knot which is not a symmetric union

Michel Boileau·Teruaki Kitano·Yuta Nozaki
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Abstract

A basic open question motivated by the study of ribbon knot diagrams asks whether every ribbon knot can be presented as a symmetric union. In this article, we give a negative answer to this question by exhibiting a ribbon Montesinos knot which does not admit a symmetric union presentation.

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Michel Boileau, Teruaki Kitano, Yuta Nozaki. 2026-06-02. A ribbon knot which is not a symmetric union. https://arxiv.org/abs/2606.02968

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