Ars Combinatoria

ISSN 0381-7032 (print), 2817-5204 (online)

Ars Combinatoria is the oldest Canadian journal of combinatorics, established in 1976, dedicated to advancing combinatorial mathematics through the publication of high-quality, peer-reviewed research papers. Over the decades, it has built a strong international reputation and continues to serve as a leading platform for significant contributions to the field.
Open Access:  The journal follows the Diamond Open Access model—completely free for both authors and readers, with no article processing charges (APCs)
Publication Frequency: From 2024 onward, Ars Combinatoria publishes four issues annually—in March, June, September, and December.
Scope: Publishes research in all areas of combinatorics, including graph theory, design theory, enumeration, algebraic combinatorics, combinatorial optimization and related fields.
Indexing & Abstracting:  Indexed in MathSciNet, Zentralblatt MATH, and EBSCO, ensuring wide visibility and scholarly reach.
Rapid Publication: Submissions are processed efficiently, with accepted papers published promptly in the next available issue.
Print & Online Editions: Issues are available in both print and online formats to serve a broad readership.

Xuemei Liu1, Yuting Xiao2, You Gao2
1College of Science, Civil Aviation University of Chi- na,Tianjin,300300, P.R.China
2College of Science, Civil Aviation University of China, Tianjin, 300300, P.R.China
Abstract:

Let \(\text{ASG}(2v+1,v;\mathbb{F}_q)\) be the \((2v+1)\)-dimensional affine-singular symplectic space over the finite field \(\mathbb{F}_q\) and let \(\text{ASp}_{2v+1}(\mathbb{F}_q)\) be the affine-singular symplectic group of degree \(2v+1\) over \(\mathcal{F}_q\). For any orbit \(O\) of flats under \(\text{ASp}_{2v+1}(\mathbb{F}_q)\), let \(\mathcal{L}\) be the set of all flats which are intersections of flats in \(O\) such that \(O \subseteq \mathcal{L}\) and assume the intersection of the empty set of flats in \(\text{ASG}(2v+1,v;\mathbb{F}_q)\) is \(\mathbb{F}_q^{2v+1}\). By ordering \(\mathcal{L}\) by ordinary or reverse inclusion, two lattices are obtained. This article discusses the relations between different lattices, classifies their geometricity, and computes their characteristic polynomial.

Jordy Vanpoucke1
1 Vakekerkweg 43, 9990 Belgium, Europe
Zhao Chengye1, Cao Feilong1
1 College of Science, China Jiliang University, Hangzhou, 310018, P.R.China
Abstract:

Let \(\gamma_c(G)\) be the connected domination number of \(G\).A graph is \(k\)-\(\gamma_c\)-critical if \(\gamma_c(G) = k\) and \(\gamma_c(G + uv) < \gamma_c(G)\) for any nonadjacent pair of vertices \(u\) and \(v\) in the graph \(G\). In this paper, we show that the diameter of a \(k\)-\(\gamma_c\)-critical graph is at most \(k\) and this upper bound is sharp.

Ramin Javadi1, Behnaz Omoomi1
1Department of Mathematical Sciences Isfahan University of Technology 84156-88111, Isfahan, Iran
Abstract:

A \(b\)-coloring of a graph \(G\) by \(k\) colors is a proper \(k\)-coloring of the vertices of \(G\) such that in each color class there exists a vertex having neighbors in all the other \(k-1\) color classes. The \(b\)-chromatic number \(\varphi(G)\) of a graph \(G\) is the maximum \(k\) for which \(G\) has a \(b\)-coloring by \(k\) colors. This concept was introduced by R.W. Irving and D.F. Manlove in \(1999\). In this paper, we study the \(b\)-chromatic numbers of the cartesian products of paths and cycles with complete graphs and the cartesian product of two complete graphs.

Huiping Cai1,2, Juan Liu1, Jixiang Meng3
1College of Mathemetics Sciences, Xinjiang Normal University, Urumgi, Xinjiang, 880054, P.R.China
2Department of Mathematics, School of Sctence,Shihezi University, Shihezi,Xingiang 882008, P.R.China
3College of Mathematics and System Sciences, Xinjiang University, Urumgi, Xinjiang, 830046, P.R.China
Abstract:

Let \(K_{d,d}\) be a complete bipartite digraph. In this paper, we determine the exact value of the domination number in iterated line digraph of \(K_{d,d}\).

Zhi-wen Wang1,2,3, Li-Hong Yan2,3, Jaeun Lee1, Zhong-fu Zhang4
1College of Mathematics and Computer, Ningxia University, Ningxia, 750021, China.
2Department of Mathematics of Yeungnam University, Daedong, Kyongsan, Kyongbuk 712-749, Korea,
3Department of Mathematics of Xianyang Norma] University, Xianyang,Shangxi, 712000, P.R.China
4Department of Mathematics of Lanzhou Jiaotong University, Lanzhou, Gansu, 730070, P.R.China
Abstract:

A total coloring of a simple graph \(G\) is called adjacent vertex distinguishing if for any two adjacent and distinct vertices \(u\) and \(v\) in \(G\), the set of colors assigned to the vertices and the edges incident to \(u\) differs from the set of colors assigned to the vertices and the edges incident to \(v\). In this paper, we shall prove that the adjacent vertex distinguishing total chromatic number of an outer plane graph with \(\Delta \leq 5\) is \(\Delta+2\) if \(G\) has two adjacent maximum degree vertices, otherwise it is \(\Delta+1\).

Neville Robbins1
1Mathematics Department San Francisco State University San Francisco, CA 94132 USA
Abstract:

Let \(P_j(n)\) denote the number of representations of \(n\) as a sum of \(j\) pentagonal numbers. We obtain formulas for \(P_j(n)\) when \(j = 2\) and \(j = 3\).

William F.Klostermeyer1, C.M. Mynhardt2
1School of Computing University of North Florida Jacksonville, FL 32224-2669
2Department of Mathematics and Statistics University of Victoria, P.O. Box 3060 STN CSC Victoria, BC, CANADA V8W 3R4
Abstract:

Eternal domination of a graph requires the vertices of the graph to be protected, against infinitely long sequences of attacks, by guards located at vertices, with the requirement that the configuration of guards induces a dominating set at all times. We study some variations of this concept in which the configuration of guards induce total dominating sets. We consider two models of the problem: one in which only one guard moves at a time and one in which all guards may move simultaneously. A number of upper and lower bounds are given for the number of guards required.

Guohui Hao1, Qingde Kang1
1 Institute of Math., Hebei Normal University Shijiazhuang 050024, P.R. China
Abstract:

Let \(G\) be a finite graph and \(H\) be a subgraph of \(G\). If \(V(H) = V(G)\) then the subgraph is called a spanning subgraph of \(G\). A spanning subgraph \(H\) of \(G\) is called an \(F\)-factor if each component of \(H\) is isomorphic to \(F\). Further, if there exists a subgraph of \(G\) whose vertex set is \(V(G)\) and can be partitioned into \(F\)-factors, then it is called a \(\lambda\)-fold \(F\)-factor of \(G\), denoted by \(S_\lambda(1,F,G)\). A large set of \(\lambda\)-fold \(F\)-factors of \(G\), denoted by \(LS_\lambda(1,F,G)\), is a partition \(\{\mathcal{B}_i\}_i\) of all subgraphs of \(G\) isomorphic to \(F\), such that each \((X,\mathcal{B}_i)\) forms a \(\lambda\)-fold \(F\)-factor of \(G\). In this paper, we investigate \(LS_\lambda(1,K_{1,3},K_{v,v})\) for any index \(\lambda\) and obtain existence results for the cases \(v = 4t, 2t + 1, 12t+6\) and \(v \geq 3\).

T. Kim1, D.S. Kim2, A. Bayad3, S.-H. Rim4
1 DEPARTMENT OF MATHEMATICS,, KWANGWOON UNIVERSITY, SEOUL 139-701, REPUBLIC OF Korea
2DEPARTMENT OF MATHEMATICS, SOGANG UNIVERSITY, SEOUL 121-742, Korea
3DEPARTEMENT DE MATHEMATIQUES,, UNIVERSITE D’EVRY VAL D’ESSONNE, Bp. F. MrrrerRanpb, 91025 Evry CEDEX, FRANCE
4 DEPARTMENT OF MATHEMATICS EDUCATION,, KyYUNGPOOK NATIONAL UNIVERSITY, Taecu 702-701, REPUBLIC OF Korea
Abstract:

In this paper, we give some interesting identities on the Bernoulli and the Euler numbers and polynomials by using reflection symmetric properties of Euler and Bernoulli polynomials. To derive our identities, we investigate some properties of the fermionic \(p\)-adic integrals on \(\mathbb{Z}_p\).