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20212026
most citedTwo periodicity conditions for spinal groups

1 citations · 2 across the 10 of their papers we have counts for

collaborators

13 papers

math.GR2026

Only their cardinality can prevent groups from being quotients of weakly branch groups

J. Moritz Petschick

It is a well-known fact that every proper quotient of a branch group is a virtually abelian group. We record that every group of cardinality at most is a quotient of…

math.GR2026

Representation zeta functions of split extensions of

J. Moritz Petschick, Margherita Piccolo

We consider the representation growth of split extensions of . We prove that the corresponding representation zeta functions factor as a product of the representation ze…

math.GR2025

Branch groups with many maximal subgroups

J. Moritz Petschick

This article presents the construction of finitely generated branch groups with uncountably many maximal subgroups using embedding techniques. This addresses a question posed by Gr…

math.GR2025

Conciseness of first-order formulae

Martina Conte, Jan Moritz Petschick

A word is concise in a class of groups if, for every group in , the verbal subgroup is finite whenever takes only finitely many values…

math.GR2024

Maximal subgroups in torsion branch groups

Mikel Eguzki Garciarena, J. Moritz Petschick

We study the maximal subgroups of branch groups and obtain a criterion that ensures that certain spinal groups are contained in the class of groups with all maximal…

math.GR2023

On finitely generated Engel branch groups

Jan Moritz Petschick

We construct finitely generated Engel branch groups, answering a question of Fernández-Alcober, Noce and Tracey on the existence of such objects. In particular, the groups construc…

math.GR2022

The automorphism group of a multi-GGS group

Jan Moritz Petschick

A multi-GGS-group is a group of automorphisms of a regular rooted tree, generalising the Gupta--Sidki -groups. We compute the automorphism groups of all non-constant multi-GGS-g…

math.GR2022

The derived series of GGS-groups

Jan Moritz Petschick

Given a GGS-group with non-constant defining tuple over a prime-regular rooted tree, we calculate the indices and describe the structure of the higher derived sub…

math.GR2022

Free polynilpotent groups and the Magnus property

Benjamin Klopsch, Luis Mendonça, Jan Moritz Petschick

Motivated by a classic result for free groups, one says that a group has the Magnus property if the following holds: whenever two elements generate the same normal subgroup of…

math.GR2022★ 1 cited

Conjugacy classes of polyspinal groups

Jan Moritz Petschick, Anitha Thillaisundaram

Spinal groups and multi-GGS groups are both generalisations of the well-known Grigorchuk-Gupta-Sidki (GGS-)groups. Here we give a necessary condition for spinal groups to be conjug…

math.GR2022

Groups of small period growth

Jan Moritz Petschick

We construct finitely generated groups of small period growth, i.e. groups where the maximum order of an element of word length grows very slowly in . This answers a questio…

math.GR2021★ 1 cited

Two periodicity conditions for spinal groups

Jan Moritz Petschick

A constant spinal group is a subgroup of the automorphism group of a regular rooted tree, generated by a group of rooted automorphisms and a group of directed automorphisms …

math.GR2021

On the Basilica Operation

Jan Moritz Petschick, Karthika Rajeev

Inspired by the Basilica group , we describe a general construction which allows us to associate to any group of automorphisms of a roote…