Sutured Heegaard diagrams for knots
نویسندگان
چکیده
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 socalled “semifibred" satellite knots, the top filtration term of the knot Floer homology is isomorphic to the counterpart of the companion.
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