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Sutured Heegaard diagrams for knots

Yi Ni
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Abstract

We define sutured Heegaard diagrams for null-homologous knots in 3-manifolds. These diagrams are useful for computing the knot Floer homology at the top filtration level. As an application, we give a formula for the knot Floer homology of a Murasugi sum. Our result echoes Gabai's earlier works. We also show that for so-called 'semifibred' satellite knots, the top filtration term of the knot Floer homology is isomorphic to the counterpart of the companion.

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Yi Ni. 2009-03-10. Sutured Heegaard diagrams for knots. https://doi.org/10.2140/agt.2006.6.513

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