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arXiv · 2104.14687

The next-to-top term in knot Floer homology

Abstract

Let $K$ be a null-homologous knot in a generalized L-space $Z$ with $b_1(Z)\le1$. Let $F$ be a Seifert surface of $K$ with genus $g$. We show that if $\widehat{HFK}(Z,K,[F],g)$ is supported in a single $\mathbb Z/2\mathbb Z$--grading, then \[\mathrm{rank}\widehat{HFK}(Z,K,[F],g-1)\ge\mathrm{rank}\widehat{HFK}(Z,K,[F],g).\]

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Yi Ni. 2021-04-29. The next-to-top term in knot Floer homology. https://arxiv.org/abs/2104.14687

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