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The Casson-Walker-Lescop Invariant and Link Invariants

Jeff Johannes
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Abstract

Formulas previously presented for the Casson-Walker invariant are generalized to Lescop's extension. These formulas in terms of linking numbers and surgery coefficients compute the change in Lescop's invariant under crossing changes in a framed link presenting a 3-manifold. This leads us to revisit an old formula for a coefficient of the Conway polynomial. Finally we compute Lescop's invariant of several lens spaces and deduce some values for Dedekind sums.

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Jeff Johannes. 2000-07-11. The Casson-Walker-Lescop Invariant and Link Invariants. https://arxiv.org/abs/math/0007064

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