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arXiv · 1811.06432

A fast algorithm for calculating $s$-invariants

Dirk Schuetz
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Abstract

We use the divide-and-conquer and scanning algorithms for calculating Khovanov cohomology directly on the Lee- or Bar-Natan deformations of the Khovanov complex to give an alternative way to compute Rasmussen $s$-invariants of knots. By disregarding generators away from homological degree 0 we can considerably improve the efficiency of the algorithm. With a slight modification we can also apply it to a refinement of Lipshitz-Sarkar.

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Dirk Schuetz. 2018-11-15. A fast algorithm for calculating $s$-invariants. https://arxiv.org/abs/1811.06432

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