Khovanov Homology and the Twist Number of Alternating Knots

Robert G. Todd

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arXiv · math/0609314

Khovanov Homology and the Twist Number of Alternating Knots

Robert G. Todd

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Abstract

X.S. Lin and O. Dasbach proved that the sum of the absolute value of the second and penultimate coefficients of the Jones polynomial of an alternating knot is equal to the twist number of the knot. In this paper we give a new proof of their result using Khovanov homology. The proof is by induction on the number of crossings using the long exact sequence in Khovanov homology corresponding to the Kauffman bracket skein relation.

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Robert G. Todd. 2006-09-11. Khovanov Homology and the Twist Number of Alternating Knots. https://arxiv.org/abs/math/0609314

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