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The metric dimension of non-component graph, associated to a finite vector space, is determined. It is proved that the exchange property holds for resolving sets of the graph, except a special case. Some results are also related to an…

Combinatorics · Mathematics 2016-03-22 Usman Ali , Syed Ahtisham Bokhary , Khola Wahid

We present a construction of Neumaier graphs with nexus 1, which generalises two known constructions of Neumaier graphs. We also use W. Wang, L. Qiu, and Y. Hu switching to show that we construct cospectral Neumaier graphs. Finally, we show…

Combinatorics · Mathematics 2023-02-14 Rhys J. Evans , Sergey Goryainov , Elena V. Konstantinova , Alexander D. Mednykh

The Cheeger constant of a graph, or equivalently its coboundary expansion, quantifies the expansion of the graph. This notion assumes an implicit choice of a coefficient group, namely, $\mathbb{F}_2$. In this paper, we study Cheeger-type…

Combinatorics · Mathematics 2025-04-29 Uriya A. First , Tali Kaufman

We prove that the ordered configuration spaces of planar graphs have the highest possible topological complexity generically, as predicted by a conjecture of Farber. Our argument establishes the same generic maximality for all higher…

Algebraic Topology · Mathematics 2021-08-03 Ben Knudsen

This note is a continuation of an earlier paper by the authors. We describe improved constructions addressing a question of Erd\H{o}s and Szemer\'edi on sums and products of real numbers along the edges of a graph. We also add a few…

Combinatorics · Mathematics 2023-08-01 Noga Alon , Imre Ruzsa , Jozsef Solymosi

Complex systems have motivated continuing interest from the scientific community, leading to new concepts and methods. Growing systems represent a case of particular interest, as their topological, geometrical, and also dynamical properties…

Social and Information Networks · Computer Science 2024-05-27 Alexandre Benatti , Roberto M. Cesar , Luciano da F. Costa

We study Gibbs partitions that typically form a unique giant component. The remainder is shown to converge in total variation toward a Boltzmann-distributed limit structure. We demon- strate how this setting encompasses arbitrary weighted…

Combinatorics · Mathematics 2016-12-15 Benedikt Stufler

In this note, we give a self-contained and elementary proof of the elementary construction of spectral high-dimensional expanders using elementary matrices due to Kaufman and Oppenheim [Proc. 50th ACM Symp. on Theory of Computing (STOC),…

Discrete Mathematics · Computer Science 2022-06-02 Prahladh Harsha , Ramprasad Saptharishi

In this paper we show that graphs of "neighbourly" cubical complexes -- cubical complexes in which every pair of vertices spans a (unique) cube -- have good expansion properties, using a technique based on multicommodity flows. By showing…

Combinatorics · Mathematics 2007-05-23 Thomas Voigt

In this note, we give short inductive proofs of two known results on $k$-extendible graphs based on a property proved in [Qinglin Yu, A note on $n$-extendable graphs. Journal of Graph Theory, 16:349-353, 1992].

Combinatorics · Mathematics 2021-10-08 Shenwei Huang , Yongtang Shi

Partial cubes are isometric subgraphs of hypercubes. Structures on a graph defined by means of semicubes, and Djokovi\'{c}'s and Winkler's relations play an important role in the theory of partial cubes. These structures are employed in the…

Combinatorics · Mathematics 2007-05-23 Sergei Ovchinnikov

Partial duality is a duality of ribbon graphs relative to a subset of their edges generalizing the classical Euler-Poincare duality. This operation often changes the genus. Recently J.L.Gross, T.Mansour, and T.W.Tucker formulated a…

Combinatorics · Mathematics 2021-07-06 Sergei Chmutov , Fabien Vignes-Tourneret

This paper presents a phenomenon which sometimes occurs in tetravalent bipartite locally dart-transitive graphs, called a Base Graph -- Connection Graph dissection. In this dissection, each white vertex is split into two vertices of valence…

Combinatorics · Mathematics 2020-04-07 Gabriel Verret , Primož Potočnik , Steve Wilson

Computing a morph between two drawings of a graph is a classical problem in computational geometry and graph drawing. While this problem has been widely studied in the context of planar graphs, very little is known about the existence of…

Computational Geometry · Computer Science 2021-05-28 Patrizio Angelini , Michael A. Bekos , Fabrizio Montecchiani , Maximilian Pfister

We present sweeping line graphs, a generalization of $\Theta$-graphs. We show that these graphs are spanners of the complete graph, as well as of the visibility graph when line segment constraints or polygonal obstacles are considered. Our…

Computational Geometry · Computer Science 2024-01-09 Keenan Lee , André van Renssen

We define an operation of jets on graphs inspired by the corresponding notion in commutative algebra and algebraic geometry. We examine a few graph theoretic properties and invariants of this construction, including chromatic numbers,…

Combinatorics · Mathematics 2022-03-09 Federico Galetto , Elisabeth Helmick , Molly Walsh

We survey recent developments on the Restriction conjecture.

Classical Analysis and ODEs · Mathematics 2007-05-23 Terence Tao

We introduce a new concept, which we call partition expanders. The basic idea is to study quantitative properties of graphs in a slightly different way than it is in the standard definition of expanders. While in the definition of expanders…

Computational Complexity · Computer Science 2022-03-30 Dmytro Gavinsky , Pavel Pudlák

In this expository note we present a proof of the V.A. Vassiliev conjecture on the planarity of graphs with vertices of degree 4 and certain additional structure. Both statement and proof are accessible to high-school students familiar with…

Combinatorics · Mathematics 2018-10-02 Arkadiy Skopenkov

Let G be a graph with vertices V and edges E. Let F be the union-closed family of sets generated by E. Then F is the family of subsets of V without isolated points. Theorem: There is an edge e belongs to E such that |{U belongs to F | e…

Combinatorics · Mathematics 2016-09-06 Emanuel Knill