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arXiv · 1812.09553

Computing Ribbon Obstructions for Colored Knots

Patricia Cahn·Alexandra Kjuchukova
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Abstract

Kjuchukova's $Ξ_p$ invariant gives a ribbon obstruction for Fox $p$-colored knots. The invariant is derived from dihedral branched covers of 4-manifolds, and is needed to calculate the signatures of these covers, when singularities on the branching sets are present. In this note, we give an algorithm for evaluating $Ξ_p$ from a colored knot diagram, and compute a couple of examples.

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Patricia Cahn, Alexandra Kjuchukova. 2020-08-29. Computing Ribbon Obstructions for Colored Knots. https://doi.org/10.4064/fm767-7-2020

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