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arXiv · 1509.08039

Fredholm theory for cofinite sets

P. L. Robinson
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Abstract

We investigate two ways in which self-maps of an infinite set may be close to bijections; our investigation generates a $\mathbb{Z}$-valued index theory and a corresponding extension by $\mathbb{Z}$ for the quotient of the full symmetric group by its finitary subgroup.

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P. L. Robinson. 2015-09-27. Fredholm theory for cofinite sets. https://arxiv.org/abs/1509.08039

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