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arXiv · 2511.22750

The Index Problem for Subgroup Intersections

Haran Mouli
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Abstract

In previous papers, Drungilas et al. study the problem of which triples of positive integers $(a, b, c)$ can be realized as $([E: \mathbb{Q}], [F: \mathbb{Q}], [EF: \mathbb{Q}])$, where $E$ and $F$ are number fields, using techniques from field theory. We shall study this problem rephrased in the language of groups using the Galois correspondence to simplify and generalize their results.

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Haran Mouli. 2025-11-27. The Index Problem for Subgroup Intersections. https://arxiv.org/abs/2511.22750

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