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arXiv · 2603.27648

Automorphisms of a Free Centre-by-Centre-by-Metabelian Group of Rank 3

C. E. Kofinas
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Abstract

Let $F_{3}$ be the free group of rank $3$ and let $G_{3} = F_{3}/[F_{3}^{\prime\prime}, F_{3}, F_{3}]$, that is, $G_{3}$ is a free centre-by-centre-by-metabelian group of rank $3$. We show that ${\rm Aut}(G_{3})$ contains a proper finitely generated subgroup that is dense with respect to the formal power series topology.

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C. E. Kofinas. 2026-03-29. Automorphisms of a Free Centre-by-Centre-by-Metabelian Group of Rank 3. https://arxiv.org/abs/2603.27648

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