Delta-Unknotting Number for Two-Bridge Knots

Kazumichi Nakamura

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arXiv · 2512.22970

Delta-Unknotting Number for Two-Bridge Knots

Kazumichi Nakamura

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Abstract

The $\Delta$-unknotting number for a knot is defined as the minimum number of $\Delta$-moves needed to deform the knot into the trivial knot. We determine the $\Delta$-unknotting numbers for two-bridge knots of type $C(2\beta_1, 2\beta_2, ... , 2\beta_n)$ and type $C(2\beta_1, 2\beta_2, ... , 2\beta_{n-1}, 2\beta_n-1)$, where $\beta_i$ is a positive integer for $1 \leq i \leq n$. We also discuss two-bridge knots whose $\Delta$-unknotting number is equal to one.

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BibTeX RIS

Kazumichi Nakamura. 2025-12-28. Delta-Unknotting Number for Two-Bridge Knots. https://arxiv.org/abs/2512.22970

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