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Related papers: Two-arc-transitive graphs of odd order -- II

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We study the question of whether, for a given class of finite graphs, one can define, for each graph of the class, a linear ordering in monadic second-order logic, possibly with the help of monadic parameters. We consider two variants of…

Logic in Computer Science · Computer Science 2015-07-01 Achim Blumensath , Bruno Courcelle

An odd (resp. even) subgraph in a multigraph is its subgraph in which every vertex has odd (resp. even) degree. We say that a multigraph can be decomposed into two odd subgraphs if its edge set can be partitioned into two sets so that both…

Combinatorics · Mathematics 2022-09-02 Mikio Kano , Gyula Y. Katona , Kitti Varga

We classify the connected-homogeneous digraphs with more than one end. We further show that if their underlying undirected graph is not connected-homogeneous, they are highly-arc-transitive.

Combinatorics · Mathematics 2010-04-30 Matthias Hamann , Fabian Hundertmark

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

For an integer $k\geq 1$, a graph is called a $k$-circulant if its automorphism group contains a cyclic semiregular subgroup with $k$ orbits on the vertices. We show that, if $k$ is even, there exist infinitely many cubic arc-transitive…

Combinatorics · Mathematics 2016-03-07 Michael Giudici , István Kovács , Cai Heng Li , Gabriel Verret

A vertex transitive graph $\Gamma$ is said to be $2$-distance transitive if for each vertex $u$, the group of automorphisms of $\Gamma$ fixing the vertex $u$ acts transitively on the set of vertices at distance $1$ and $2$ from $u$, while…

Combinatorics · Mathematics 2024-03-05 Jun-Jie Huang , Yan-Quan Feng , Jin-Xin Zhou , Fu-Gang Yin

We study the commuting graph on elements of odd prime order in finite simple groups. The results are used in a forthcoming paper describing the structure of Bruck loops and Bol loops of exponent 2.

Group Theory · Mathematics 2009-08-19 Barbara Baumeister , Alexander Stein

In this paper, we investigate odd graceful graph, odd strongly harmonious graph, bipartite graph and their relationship. We proved following results: (1) if G is odd strongly harmonious graph, then G is odd graceful graph ;(2) if G is…

Combinatorics · Mathematics 2020-01-06 Xiuying Wang , Ying Zhoua , Haihong Wanga , Chunfeng Liu

We prove that every finite arc-transitive graph of valency twice a prime admits a nontrivial semiregular automorphism, that is, a non-identity automorphism whose cycles all have the same length. This is a special case of the Polycirculant…

Combinatorics · Mathematics 2019-01-03 Michael Giudici , Gabriel Verret

A connected graph of order $n$ admitting a semiregular automorphism of order $n/k$ is called a $k$-multicirculant. Highly symmetric multicirculants of small valency have been extensively studied, and several classification results exist for…

Combinatorics · Mathematics 2022-08-15 Primož Potočnik , Micael Toledo

In this work, we define an orthogonal graph on the set of equivalence classes of $(2\nu + \delta)-$tuples over $\mathbb{Z}_{2^n}$ where $n$ and $\nu$ are positive integers and $\delta = 0, 1$ or $2$. We classify our graph if it is strongly…

Combinatorics · Mathematics 2019-01-07 Songpon Sriwongsa

This is the second of a series of papers which aim towards a classification of edge-transitive maps of which the Euler characteristic and the edge number are coprime. This one carries out the classification work for arc-transitive maps with…

Combinatorics · Mathematics 2025-02-25 Cai Heng Li , Luyi Liu

A 2-factor of a graph is a 2-regular spanning subgraph. For a graph $G$ and an independent set $I$ of $G$, let $\delta_G(I)$ denote the minimum degree of vertices contained in $I$. We show that (1) if every independent set $I$ of $G$…

Combinatorics · Mathematics 2025-03-25 Masaki Kashima

A graph $\Ga$ is $G$-symmetric if $\Ga$ admits $G$ as a group of automorphisms acting transitively on the set of vertices and the set of arcs of $\Ga$, where an arc is an ordered pair of adjacent vertices. In the case when $G$ is…

Combinatorics · Mathematics 2013-11-27 Guangjun Xu , Sanming Zhou

we obtain a necessary condition for the character degree graph with all of its vertices are odd degree of a finite solvable group G.

Group Theory · Mathematics 2023-05-23 G. Sivanesan , C. Selvaraj

In an earlier paper the first two authors have shown that self-complementary graphs can always be oriented in such a way that the union of the oriented version and its isomorphically oriented complement gives a transitive tournament. We…

Combinatorics · Mathematics 2018-06-05 Attila Sali , Gábor Simonyi , Gábor Tardos

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

A graph $\G$ is {\em symmetric} or {\em arc-transitive} if its automorphism group $\Aut(\G)$ is transitive on the arc set of the graph, and $\G$ is {\em basic} if $\Aut(\G)$ has no non-trivial normal subgroup $N$ such that the quotient…

Combinatorics · Mathematics 2017-07-18 Da-Wei Yang , Yan-Quan Feng , Jin Ho Kwak , Jaeun Lee

Let $T$ be a locally finite tree all of whose vertices have valency at least $6$. We classify, up to isomorphism, the closed subgroups of $\mathrm{Aut}(T)$ acting $2$-transitively on the set of ends of $T$ and whose local action at each…

Group Theory · Mathematics 2020-07-23 Nicolas Radu

In this paper, we introduce a family of tetravalent graphs called propeller graphs, denoted by $Pr_{n}(b,c,d)$. We then produce three infinite subfamilies and one finite subfamily of arc-transitive propeller graphs, and show that all such…

Combinatorics · Mathematics 2016-01-05 Matthew C. Sterns