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arXiv · 2003.13273

Combinatorial approach to Milnor invariants of welded links

Haruko A. Miyazawa·Kodai Wada·Akira Yasuhara
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Abstract

For a classical link, Milnor defined a family of isotopy invariants, called Milnor $\overline{\mu}$-invariants. Recently, Chrisman extended Milnor $\overline{\mu}$-invariants to welded links by a topological approach. The aim of this paper is to show that Milnor $\overline{\mu}$-invariants can be extended to welded links by a combinatorial approach. The proof contains an alternative proof for the invariance of the original $\overline{\mu}$-invariants of classical links.

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Haruko A. Miyazawa, Kodai Wada, Akira Yasuhara. 2020-03-30. Combinatorial approach to Milnor invariants of welded links. https://arxiv.org/abs/2003.13273

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