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Related papers: On H-Irregularity Strength of Grid Graphs

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A numbering $f$ of a graph $G$ of order $n$ is a labeling that assigns distinct elements of the set $\{1,2, \ldots, n \}$ to the vertices of $G$. The strength $\mathrm{str}\left(G\right) $ of $G$ is defined by $\mathrm{str}\left( G\right)…

Combinatorics · Mathematics 2023-11-28 Rikio Ichishima , Francesc A. Muntaner-Batle , Yukio Takahashi

A perfect $H$-tiling in a graph $G$ is a collection of vertex-disjoint copies of a graph $H$ in $G$ that covers all vertices of $G$. Motivated by papers of Bush and Zhao and of Balogh, Treglown, and Wagner, we determine the threshold for…

Combinatorics · Mathematics 2024-11-20 Enrique Gomez-Leos , Ryan R. Martin

The matching number of a $k$-graph is the maximum number of pairwise disjoint edges in it. The $k$-graph is called $t$-resilient if omitting $t$ vertices never decreases its matching number. The complete $k$-graph on $sk+k-1$ vertices has…

Combinatorics · Mathematics 2025-03-12 Peter Frankl , Jian Wang

In this note a new measure of irregularity of a simple undirected graph $G$ is introduced. It is named the total irregularity of a graph and is defined as $\irr_t(G) = 1/2\sum_{u,v \in V(G)} |d_G(u)-d_G(v)|$, where $d_G(u)$ denotes the…

Discrete Mathematics · Computer Science 2015-03-20 Hosam Abdo , Darko Dimitrov

We present a method which provides a unified framework for most stability theorems that have been proved in graph and hypergraph theory. Our main result reduces stability for a large class of hypergraph problems to the simpler question of…

Combinatorics · Mathematics 2022-11-15 Xizhi Liu , Dhruv Mubayi , Christian Reiher

For a given multigraph H, a graph G is H-linked, if |G| \geq |H| and for every injective map {\tau}: V (H) \rightarrow V (G), we can find internally disjoint paths in G, such that every edge from uv in H corresponds to a {\tau} (u) - {\tau}…

Combinatorics · Mathematics 2012-06-08 Florian Pfender

A $k$-regular graph of girth $g$ is called edge-girth-regular graph, shortly egr-graph, if each of its edges is contained in exactly $\lambda$ distinct $g-$cycles. An egr-graph is called extremal for the triple $(k, g, \lambda)$ if has the…

Combinatorics · Mathematics 2024-01-30 Gabriela Araujo-Pardo , György Kiss , István Porupsánszki

In this paper, we study the behaviour of the generalized power domination number of a graph by small changes on the graph, namely edge and vertex deletion and edge contraction. We prove optimal bounds for $\gamma\_{p,k}(G-e)$,…

Discrete Mathematics · Computer Science 2016-03-24 Paul Dorbec , Seethu Varghese , Ambat Vijayakumar

The toughness $t(G)$ of a graph $G=(V,E)$ is defined as $t(G)=\min\{\frac{|S|}{c(G-S)}\}$, in which the minimum is taken over all $S\subset V$ such that $G-S$ is disconnected, where $c(G-S)$ denotes the number of components of $G-S$. We…

Combinatorics · Mathematics 2021-04-09 Xiaofeng Gu , Willem H. Haemers

The $g$-girth-thickness $\theta(g,G)$ of a graph $G$ is the minimum number of planar subgraphs of girth at least $g$ whose union is $G$. In this paper, we determine the $6$-girth-thickness $\theta(6,K_n)$ of the complete graph $K_n$ in…

In this paper, we propose a perturbation framework to measure the robustness of graph properties. Although there are already perturbation methods proposed to tackle this problem, they are limited by the fact that the strength of the…

Social and Information Networks · Computer Science 2019-01-29 Yali Wan , Marina Meila

We characterise the form of all simple, finite graphs for which the girth of the graph is equal to the circumference of the graph. We apply this to prove a bound on the number of edges in such a graph.

Combinatorics · Mathematics 2022-10-11 Lewis Stanton , Jeffrey Thompson

We investigate the \textit{group irregularity strength}, $s_g(G)$, of a graph, i.e. the least integer $k$ such that taking any Abelian group $\mathcal{G}$ of order $k$, there exists a function $f:E(G)\rightarrow \mathcal{G}$ so that the…

Combinatorics · Mathematics 2018-10-16 Marcin Anholcer , Sylwia Cichacz , Jakub Przybyło

Given a finite, simple graph $G$, the $k$-component order edge connectivity of $G$ is the minimum number of edges whose removal results in a subgraph for which every component has order at most $k-1$. In general, determining the…

Combinatorics · Mathematics 2023-10-10 Michael Yatauro

We say that a graph G is $(k,\ell)$-stable if removing $k$ vertices from it reduces its independence number by at most $\ell$. We say that G is tight $(k,\ell)$-stable if it is $(k,\ell)$-stable and its independence number equals…

Combinatorics · Mathematics 2024-02-08 Dingding Dong , Sammy Luo

We consider new parameters for conditional network vulnerability related to graph coloring. We define a network to be in operation if the chromatic number (or index) is greater than some specified value k. The parameters of interest, the…

Combinatorics · Mathematics 2022-12-05 Mia Destefano , Grace Mulry , Mason Nakamura , Rodrigo Rios , Nathan Shank

Let $G$ and $H$ be $k$-graphs ($k$-uniform hypergraphs); then a perfect $H$-packing in $G$ is a collection of vertex-disjoint copies of $H$ in $G$ which together cover every vertex of $G$. For any fixed $H$ let $\delta(H, n)$ be the minimum…

Combinatorics · Mathematics 2015-09-16 Richard Mycroft

For given a graph $H$, a graphic sequence $\pi=(d_1,d_2,...,d_n)$ is said to be potentially $H$-graphic if there exists a realization of $\pi$ containing $H$ as a subgraph. In this paper, we characterize the potentially $H$-graphic…

Combinatorics · Mathematics 2010-02-06 Lili Hu , Chunhui Lai

Let $k\geq 3$ be an integer and $G$ be a very well-covered graph with ${\rm odd-girth}(G)\geq 2k+1$. Assume that $I(G)$ is the edge ideal of $G$. We show that for every integer $s$ with $1\leq s\leq k-2$, we have ${\rm…

Commutative Algebra · Mathematics 2017-07-19 Pooran Norouzi , Seyed Amin Seyed Fakhari , Siamak Yassemi

For a graph G, its rth power G^r has the same vertex set as G, and has an edge between any two vertices within distance r of each other in G. We give a lower bound for the number of edges in the rth power of G in terms of the order of G and…

Combinatorics · Mathematics 2012-02-29 Alexey Pokrovskiy