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Related papers: On tetravalent half-arc-transitive graphs

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A graph is vertex-transitive if its automorphism group acts transitively on vertices of the graph. A vertex-transitive graph is a Cayley graph if its automorphism group contains a subgroup acting regularly on its vertices. In this paper,…

Group Theory · Mathematics 2022-03-10 Majid Arezoomand , Mohsen Ghasemi , Mohammad A. Iranmanesh

We prove that, if $\Gamma$ is a finite connected $3$-valent vertex-transitive, or $4$-valent vertex- and edge-transitive graph, then either $\Gamma$ is part of a well-understood family of graphs, or every non-identity automorphism of…

Combinatorics · Mathematics 2024-12-20 Marco Barbieri , Valentina Grazian , Pablo Spiga

In this paper, we examine the structure of vertex- and edge-transitive strongly regular graphs, using normal quotient reduction. We show that the irreducible graphs in this family have quasiprimitive automorphism groups, and prove (using…

Combinatorics · Mathematics 2009-07-10 Joy Morris , Cheryl E. Praeger , Pablo Spiga

We study groups acting vertex-transitively on connected, trivalent graphs such that stabilizers of vertices are infinite. If the action is edge-transitive, we prove that the graph has to be a tree. We analyze the case where the action is…

Combinatorics · Mathematics 2021-01-12 Arnbjörg Soffía Árnadóttir , Waltraud Lederle , Rögnvaldur G. Möller

In this paper a classification of tetravalent edge-transitive metacirculants is given. It is shown that a tetravalent edge-transitive metacirculant $\Gamma$ is a normal graph except for four known graphs. If further, $\Gamma$ is a Cayley…

Combinatorics · Mathematics 2016-03-29 Shu Jiao Song

A graph is edge-primitive if its automorphism group acts primitively on the edge set. In this short paper, we prove that a finite 2-arc-transitive edge-primitive graph has almost simple automorphism group if it is neither a cycle nor a…

Combinatorics · Mathematics 2019-01-11 Zaiping Lu

A graph is edge-primitive if its automorphism group acts primitively on the edge set, and 2-arc-transitive if its automorphism group acts transitively on the set of 2-arcs. In this paper, we present a classification for those edge-primitive…

Combinatorics · Mathematics 2020-10-09 Huan Han , Hong Ci Liao , Zai Ping Lu

A graph $\Gamma$ is said to be symmetric if its automorphism group $\rm Aut(\Gamma)$ acts transitively on the arc set of $\Gamma$. In this paper, we show that if $\Gamma$ is a finite connected heptavalent symmetric graph with solvable…

Combinatorics · Mathematics 2017-10-04 Jia-Li Du , Yan-Quan Feng , Yu-Qin Liu

A graph is edge-transitive if the natural action of its automorphism group on its edge set is transitive. An automorphism of a graph is semiregular if all of the orbits of the subgroup generated by this automorphism have the same length.…

A graph is said to be edge-transitive if its automorphism group acts transitively on its edges. It is known that edge-transitive graphs are either vertex-transitive or bipartite. In this paper we present a complete classification of all…

Combinatorics · Mathematics 2019-11-13 Heather A. Newman , Hector Miranda , Darren A. Narayan

Following Alspach and Parsons, a {\em metacirculant graph} is a graph admitting a transitive group generated by two automorphisms $\rho$ and $\sigma$, where $\rho$ is $(m,n)$-semiregular for some integers $m \geq 1$, $n \geq 2$, and where…

Combinatorics · Mathematics 2007-05-23 Dragan Marusic , Primoz Sparl

An automorphism of a graph is called quasi-semiregular if it fixes a unique vertex of the graph and its remaining cycles have the same length. This kind of symmetry of graphs was first investigated by Kutnar, Malni\v{c}, Mart\'{i}nez and…

Combinatorics · Mathematics 2021-08-02 Fu-Gang Yin , Yan-Quan Feng , Jin-Xin Zhou , A-Hui Jia

A connected graph $\Gamma=(V,E)$ of valency at least $3$ is called a basic $2$-arc-transitive graph if its full automorphism group has a subgroup $G$ with the following properties: (i) $G$ acts transitively on the set of $2$-arcs of…

Combinatorics · Mathematics 2022-10-11 Zai Ping Lu , Ruo Yu Song

In order to complete (and generalize) results of Gardiner and Praeger on 4-valent symmetric graphs (European J. Combin, 15 (1994)) we apply the method of lifting automorphisms in the context of elementary-abelian covering projections. In…

Combinatorics · Mathematics 2017-08-01 Boštjan Kuzman , Aleksander Malnič , Primož Potočnik

A non-complete graph $\Gamma$ is said to be $(G,2)$-distance transitive if $G$ is a subgroup of the automorphism group of $\Gamma$ that is transitive on the vertex set of $\Gamma$, and for any vertex $u$ of $\Gamma$, the stabilizer $G_u$ is…

Group Theory · Mathematics 2015-07-07 Brian P. Corr , Wei Jin , Csaba Schneider

A half-arc-transitive graph is a regular graph that is both vertex- and edge-transitive, but is not arc-transitive. If such a graph has finite valency, then its valency is even, and greater than $2$. In 1970, Bouwer proved that there exists…

Combinatorics · Mathematics 2015-05-12 Marston D. E. Conder , Arjana Žitnik

A graph is called cubic and tetravalent if all of its vertices have valency 3 and 4, respectively. It is called vertex-transitive and arc-transitive if its automorphism group acts transitively on its vertex-set and on its arc- set,…

Combinatorics · Mathematics 2012-01-26 Primoz Potocnik , Pablo Spiga , Gabriel Verret

We classify trivalent vertex-transitive graphs whose edge sets have a partition into a 2-factor composed of two cycles and a 1-factor that is invariant under the action of the automorphism group.

Combinatorics · Mathematics 2021-09-15 Brian Alspach , Ted Dobson , Afsaneh Khodadadpour , Primoz Šparl

A $2$-distance-transitive graph is a vertex-transitive graph whose vertex stabilizer is transitive on both the first step and the second step neighborhoods. In this paper, we first answer a question of A. Devillers, M. Giudici, C. H. Li and…

Combinatorics · Mathematics 2025-08-05 Wei Jin , Jack H. Koolen , Chenhui Lv

We extend the notion of an $H$-normal quotient digraph of an $H$-vertex-transitive digraph to that of an $H$-subnormal quotient digraph. Using these concepts, together with bipartite halves of bipartite digraphs, we show that, for each…

Combinatorics · Mathematics 2025-12-22 Lei Chen , Cheryl Praeger