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Related papers: On the diameter of Kronecker graphs

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We show that if a graph is k-edge-connected, and we adjoin to it another graph satisfying a "contracted diameter less or equal to 2" condition, with minimal degree greater or equal to k, and some natural hypothesis on the edges connecting…

General Mathematics · Mathematics 2008-12-18 José Ignacio Alvarez-Hamelin , Jorge Rodolfo Busch

Among other things, it is shown that for every pair of positive integers $r$, $d$, satisfying $1<r<d\leq 2r$, and every finite simple graph $H,$ there is a connected graph $G$ with diameter $d$, radius $r$, and center $H.$

Combinatorics · Mathematics 2021-11-02 Kelly Guest , Andrew Johnson , Peter Johnson , William Jones , Yuki Takahashi , Zhichun Joy Zhang

We show that the diameter D(G_n) of a random labelled connected planar graph with n vertices is equal to n^{1/4+o(1)}, in probability. More precisely there exists a constant c>0 such that the probability that D(G_n) lies in the interval…

Combinatorics · Mathematics 2019-02-20 Guillaume Chapuy , Éric Fusy , Omer Giménez , Marc Noy

Contraction-critical graphs came from the study of minimal counterexamples to Hadwiger's conjecture. A graph is $k$-contraction-critical if it is $k$-chromatic, but any proper minor is $(k-1)$-colorable. It is a long-standing result of…

Combinatorics · Mathematics 2025-09-10 Michael Lafferty , Runrun Liu , Martin Rolek , Gexin Yu

In this paper it is proved that there are constants 0< c_2< c_1 such that an asymptotic formula can be given for the the number of (labeled) n-vertex graphs of diameter d whenever n tends to infinity and 2 < d < n - c_1 (log n). A typical…

Combinatorics · Mathematics 2012-04-23 Zoltan Furedi , Younjin Kim

In this article we derive an explicit diameter bound for graphs satisfying the so-called curvature dimension conditions $CD(K,n)$. This refines a recent result due to Liu, M\"unch and Peyerimhoff when the dimension $n$ is finite.

Combinatorics · Mathematics 2024-05-21 Yi C. Huang , Ze Yang

Given a finite group $G$, the Engel graph of $G$ is a directed graph $\Gamma(G)$ encoding pairs of elements satisfying some Engel word. Namely, $\Gamma(G)$ is the directed graph, where the vertices are the non-hypercentral elements of $G$…

Group Theory · Mathematics 2023-11-09 Andrea Lucchini , Pablo Spiga

Stochastic Kronecker graphs are a model for complex networks where each edge is present independently according the Kronecker (tensor) product of a fixed matrix k-by-k matrix P with entries in [0,1]. We develop a novel correspondence…

Combinatorics · Mathematics 2015-04-02 Mary Radcliffe , Stephen J. Young

We give a combinatorial proof of the following theorem. Let $G$ be any finite group acting transitively on a set of cardinality $n$. If $S \subseteq G$ is a random set of size $k$, with $k \geq (\log n)^{1+\varepsilon}$ for some…

Combinatorics · Mathematics 2025-05-01 Daniele Dona , Luca Sabatini

In this paper we present the super connectivity of Kronecker product of a general graph and a complete graph.

Combinatorics · Mathematics 2011-05-10 Hechao Wang , Erfang Shan

We give a simplified version of the proofs that, outside of their isolated vertices, the complement of the enhanced power graph and of the power graph are connected of diameter at most $3$.

Group Theory · Mathematics 2024-11-11 Marco Barbieri , Kamilla Rekvényi

We show that the diameter of a uniformly drawn spanning tree of a simple connected graph on $n$ vertices with minimal degree linear in $n$ is typically of order $\sqrt{n}$. A byproduct of our proof, which is of independent interest, is that…

Probability · Mathematics 2021-08-12 Noga Alon , Asaf Nachmias , Matan Shalev

For integers $k \geq 2$ and $n \geq k+1$, we prove the following: If $n\cdot k$ is even, there is a connected $k$-regular graph on $n$ vertices. If $n\cdot k$ is odd, there is a connected nearly $k$-regular graph on $n$ vertices.

Combinatorics · Mathematics 2018-01-26 Ghurumuruhan Ganesan

The thickness of a graph $G$ is the minimum number of planar subgraphs whose union is $G$. In this paper, we present sharp lower and upper bounds for the thickness of the Kronecker product $G\times H$ of two graphs $G$ and $H$. We also give…

Combinatorics · Mathematics 2019-01-25 Xia Guo , Yan Yang

We conjecture that finite graphs with positive Cheeger constant admit a spanning subgraph with positive Cheeger constant and girth proportional to the diameter. We prove this conjecture for regular expander graphs with large expansion. Our…

Combinatorics · Mathematics 2021-12-04 Itai Benjamini , Mikolaj Fraczyk , Gabor Kun

For a division ring D, finite dimensional over its center F, we give a condiction for the connectedness of the commuting graph of a matrix ring over $D$. Furthermore, we prove that if the commuting graph is connected, then its diameter is…

Rings and Algebras · Mathematics 2016-10-31 C. Miguel

Let $G_1$ and $G_2$ be two undirected nontrivial graphs. The Kronecker product of $G_1$ and $G_2$ denoted by $G_1\otimes G_2$ with vertex set $V(G_1)\times V(G_2)$, two vertices $x_1x_2$ and $y_1y_2$ are adjacent if and only if…

Combinatorics · Mathematics 2012-04-19 Fu-Tao Hu , Jun-Ming Xu

Consider the Cayley graph of the cyclic group of prime order q with k uniformly chosen generators. For fixed k, we prove that the diameter of said graph is asymptotically (in q) of order q^(1/k). The same also holds when the generating set…

Probability · Mathematics 2009-10-04 Gideon Amir , Ori Gurel-Gurevich

We review Heisenberg homology of configurations in once bounded surfaces and extend the construction to the regular thickening of a finite graph with ribbon structure.

Geometric Topology · Mathematics 2025-02-11 Christian Blanchet

Let $G$ and $H$ be graphs, and $G\boxtimes H$ the strong product of $G$ and $H$. We prove that for any connected graphs $G$ and $H$ there is a strongly connected orientation $D$ of $G\boxtimes H$ such that ${\rm diam}(D)\leq 2r+15$, where…

Combinatorics · Mathematics 2019-11-22 Simon Špacapan , Irena Hrastnik-Ladinek
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