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arXiv · 1608.02085

An axiomatizable profinite group with infinitely many open subgroups of index 2

Or Ben Porath·Mark Shusterman
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Abstract

We show that a profinite group with the same first-order theory as the direct product over all odd primes $p$ of the dihedral group of order $2p$, is necessarily isomorphic to this direct product.

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Or Ben Porath, Mark Shusterman. 2016-08-06. An axiomatizable profinite group with infinitely many open subgroups of index 2. https://arxiv.org/abs/1608.02085

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