Osaka Journal of Mathematics

A note on knots with $\mathrm{H}(2)$-unknotting number one

Yuanyuan Bao

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We give an obstruction to unknotting a knot by adding a twisted band, derived from Heegaard Floer homology.

Article information

Osaka J. Math., Volume 51, Number 3 (2014), 585-597.

First available in Project Euclid: 23 October 2014

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Mathematical Reviews number (MathSciNet)

Zentralblatt MATH identifier

Primary: 57M27: Invariants of knots and 3-manifolds 57M25: Knots and links in $S^3$ {For higher dimensions, see 57Q45}


Bao, Yuanyuan. A note on knots with $\mathrm{H}(2)$-unknotting number one. Osaka J. Math. 51 (2014), no. 3, 585--597.

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