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Related papers: Cayley automatic groups are not Cayley biautomatic

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A finite group R is a CI-group if, whenever S and T are subsets of R with the Cayley graphs Cay(R,S) and Cay(R,T) isomorphic, there exists an automorphism x of R with S^x=T. The classification of CI-groups is an open problem in the theory…

Combinatorics · Mathematics 2014-02-20 Edward Dobson , Joy Morris , Pablo Spiga

In this paper, firstly, we provide some necessary and sufficient conditions for generalized Cayley graphs on abelian groups to be bipartite. Secondly, we deduce several necessary and sufficient conditions for generalized Cayley graphs on…

Combinatorics · Mathematics 2024-12-18 Liao Qianfen , Liu Weijun , Zhang Pengli

The notions of nonpositive curved spaces and biautomatic groups are generalizations of the geometric properties of hyperbolic spaces and computational properties of their fundamental groups. Given the mutual origins of these conditions, one…

Group Theory · Mathematics 2011-11-15 Rena M. H. Levitt

In this paper we address the problem of quantitative classification of Cayley automatic groups in terms of a certain numerical characteristic which we earlier introduced for this class of groups. For this numerical characteristic we…

Group Theory · Mathematics 2019-07-30 Dmitry Berdinsky , Phongpitak Trakuldit

We discuss the isomorphism problem for ergodic actions of locally compact groups. In particular we show that the conjugacy relation is not Borel for ergodic measure preserving actions of indicable groups.

Dynamical Systems · Mathematics 2025-07-10 Matthew Foreman , Benjamin Weiss

In this paper we introduce a new species of evolution algebras that we call Cayley evolution algebras. We show that if a field $k$ contains sufficiently many elements (for example if $k$ is infinite) then every finite group $G$ is…

Rings and Algebras · Mathematics 2023-03-10 Cristina Costoya , Vicente Muñoz , Alicia Tocino , Antonio Viruel

We construct an infinite family of triples (G,S1, S2) each consisting of a group G and a pair (S1, S2) of distinct subsets of G with the following properties. i The two Cayley graphs Cay(G, S1) and Cay(G,S2) are non-isomorphic. ii The…

Combinatorics · Mathematics 2025-05-07 Masao Ishikawa , Fumihiko Nakano , Taizo Sadahiro

Let $\Gamma=\mathrm{Cay}(G,S)$ be a Cayley digraph on a group $G$ and let $A=\mathrm{Aut}(\Gamma)$. The Cayley index of $\Gamma$ is $|A:G|$. It has previously been shown that, if $p$ is a prime, $G$ is a cyclic $p$-group and $A$ contains a…

Combinatorics · Mathematics 2017-03-08 Luke Morgan , Joy Morris , Gabriel Verret

A finite group $G$ is called a DCI-group if two Cayley digraphs over $G$ are isomorphic if and only if their connection sets are conjugate by a group automorphism. We prove that the group $C_4\times C_p^2$, where $p$ is a prime, is a…

Combinatorics · Mathematics 2021-05-26 Grigory Ryabov

Cayley graphs are graphs on algebraic structures, typically groups or group-like structures. In this paper, we have obtained a few results on Cayley graphs on Cyclic groups, powers of cycles, Cayley graphs on some non-abelian groups, and…

Combinatorics · Mathematics 2023-08-23 Prajnanaswaroopa S

Using a novel rewriting problem, we show that several natural decision problems about finite automata are undecidable (i.e., recursively unsolvable). In contrast, we also prove three related problems are decidable. We apply one result to…

Formal Languages and Automata Theory · Computer Science 2017-03-01 Jörg Endrullis , Jeffrey Shallit , Tim Smith

We show that every finitely generated group G with an element of order at least $(5rank(G))^{12}$ admits a locally finite directed Cayley graph with automorphism group equal to G. If moreover G is not generalized dihedral, then the above…

Combinatorics · Mathematics 2025-04-02 Paul-Henry Leemann , Mikael de la Salle

The isomorphism problem for [free abelian]-by-free groups is unsolvable.

Group Theory · Mathematics 2008-12-15 Gilbert Levitt

We construct an infinite family of connected, 2-generated Cayley digraphs Cay(G;a,b) that do not have hamiltonian paths, such that the orders of the generators a and b are arbitrarily large. We also prove that if G is any finite group with…

Combinatorics · Mathematics 2013-06-25 Dave Witte Morris

A binary Cayley graph is a Cayley graph based on a binary group. In 1982, Payan proved that any non-bipartite binary Cayley graph must contain a generalized Mycielski graph of an odd-cycle, implying that such a graph cannot have chromatic…

Combinatorics · Mathematics 2015-02-04 Laurent Beaudou , Reza Naserasr , Claude Tardif

Let $G$ be a finite non-abelian simple group, $C$ a non-identity conjugacy class of $G$, and $\Gamma_C$ the Cayley graph of $G$ based on $C \cup C^{-1}$. Our main result shows that in any such graph, there is an involution at bounded…

Group Theory · Mathematics 2024-10-04 Daniele Dona , Martin W. Liebeck , Kamilla Rekvényi

We prove that the group $C_p^4\times C_q$ is a DCI-group for distinct primes $p$ and $q$, that is, two Cayley digraphs over $C_p^4 \times C_q$ are isomorphic if and only if their connection sets are conjugate by a group automorphism.

Combinatorics · Mathematics 2022-01-11 István Kovács , Grigory Ryabov

In this paper, we consider the automorphism groups of the Cayley graph with respect to the Coxeter generators and the Davis complex of an arbitrary Coxeter group. We determine for which Coxeter groups these automorphism groups are discrete.…

Group Theory · Mathematics 2012-03-01 Graham White

A map is a connected topological graph $\Gamma$ cellularly embedded in a surface. In this paper, applying Tutte's algebraic representation of map, new ideas for enumerating non-equivalent orientable or non-orientable maps of graph are…

General Mathematics · Mathematics 2009-09-29 Linfan Mao , Yanpei Liu

A Cayley graph for a group $G$ is CCA if every automorphism of the graph that preserves the edge-orbits under the regular representation of $G$ is an element of the normaliser of $G$. A group $G$ is then said to be CCA if every connected…

Group Theory · Mathematics 2017-03-24 Luke Morgan , Joy Morris , Gabriel Verret
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