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A FAST ALGORITHM FOR CALCULATING S-INVARIANTS

  • DIRK SCHÜTZ (a1)

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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A FAST ALGORITHM FOR CALCULATING S-INVARIANTS

  • DIRK SCHÜTZ (a1)

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