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arXiv · 1201.1735

When is region crossing change an unknotting operation?

Zhiyun Cheng
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Abstract

In this paper, we prove that region crossing change on a link diagram is an unknotting operation if and only if the link is proper. A description of the behavior of region crossing change on link diagrams is given. Furthermore we also discuss the relation between region crossing change and the Arf invariant of proper links.

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Zhiyun Cheng. 2012-01-09. When is region crossing change an unknotting operation?. https://doi.org/10.1017/s0305004113000236

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