The column group and its link invariants

Johanna Hennig; Sam Nelson

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arXiv · 0902.0028

The column group and its link invariants

Johanna Hennig·Sam Nelson

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Abstract

The column group is a subgroup of the symmetric group on the elements of a finite blackboard birack generated by the column permutations in the birack matrix. We use subgroups of the column group associated to birack homomorphisms to define an enhancement of the integral birack counting invariant and give examples which show that the enhanced invariant is stronger than the unenhanced invariant.

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Johanna Hennig, Sam Nelson. 2009-01-30. The column group and its link invariants. https://arxiv.org/abs/0902.0028

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