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arXiv · 2609.14522

Delta-Unknotting Number for Montesinos Knots

Kazumichi Nakamura
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Abstract

The $Δ$-unknotting number for a knot is defined as the minimum number of $Δ$-moves needed to deform the knot into the trivial knot. In this paper, we determine the $Δ$-unknotting numbers for certain families of Montesinos knots. Using results on pretzel knots and two-bridge knots, we prove that for these families the $Δ$-unknotting number equals the absolute value of the second coefficient of the Conway polynomial. In particular, every positive pretzel knot belongs to these families, and certain two-bridge knots also belong to them.

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Kazumichi Nakamura. 2026-09-13. Delta-Unknotting Number for Montesinos Knots. https://arxiv.org/abs/2609.14522

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