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arXiv · 2502.20652

The Andreadakis Problem for the McCool groups

Jaques Darné·Naoya Enomoto·Takao Satoh
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Abstract

In this short paper, we show that the McCool group does not satisfy the Andreadakis equality from degree $7$, and we give a lower bound for the size of the difference between the two relevant filtrations. As a consequence, we see that the Andreadakis problem for the McCool group does not stabilize.

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Jaques Darné, Naoya Enomoto, Takao Satoh. 2025-02-28. The Andreadakis Problem for the McCool groups. https://arxiv.org/abs/2502.20652

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