Efficient calculations of $S$-invariants for links

Dirk Schuetz

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arXiv · 2508.11373

Efficient calculations of $S$-invariants for links

Dirk Schuetz

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Abstract

We describe an algorithm that can effectively calculate the $s$-invariant of a link as defined by Beliakova and Wehrli. Our computations show that this cannot be done by merely calculating the $E_\infty$-page of the Bar-Natan--Lee--Turner spectral sequence. Our methods also work for $s$-invariants coming from sl(3)-link homology.

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Dirk Schuetz. 2025-08-15. Efficient calculations of $S$-invariants for links. https://arxiv.org/abs/2508.11373

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