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Related papers: A unified approach to total irregular labeling

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We investigate the \textit{edge group irregularity strength} ($es_g(G)$) of graphs, i.e. the smallest value of $s$ such that taking any Abelian group $\mathcal{G}$ of order $s$, there exists a function $f:V(G)\rightarrow \mathcal{G}$ such…

Combinatorics · Mathematics 2018-08-31 Marcin Anholcer , Sylwia Cichacz

Total variation (TV) is a powerful regularization method that has been widely applied in different imaging applications, but is difficult to apply to diffuse optical tomography (DOT) image reconstruction (inverse problem) due to complex and…

Computer Vision and Pattern Recognition · Computer Science 2019-04-08 Wenqi Lu , Jinming Duan , David Orive-Miguel , Lionel Herve , Iain B Styles

This paper deals with three graph characteristics related to graph covering named the (vertex, edge, and total, resp.) H-irregularity strength of a graph G admitting H-covering. Those are the minimum values of positive integer k such that G…

Combinatorics · Mathematics 2021-10-22 Meilin Imelda Tilukay

The $\sigma_{t}$-irregularity (or sigma total index) is a graph invariant which is defined as $\sigma_{t}(G)=\sum_{\{u,v\}\subseteq V(G)}(d(u)-d(v))^{2},$ where $d(z)$ denotes the degree of $z$. This irregularity measure was proposed by R\'…

Combinatorics · Mathematics 2024-11-08 Slobodan Filipovski , Darko Dimitrov , Martin Knor , Riste Škrekovski

Even after over two decades, the total variation (TV) remains one of the most popular regularizations for image processing problems and has sparked a tremendous amount of research, particularly to move from scalar to vector-valued…

Computer Vision and Pattern Recognition · Computer Science 2016-06-21 Joan Duran , Michael Moeller , Catalina Sbert , Daniel Cremers

Graph-based models form a fundamental aspect of data representation in Data Sciences and play a key role in modeling complex networked systems. In particular, recently there is an ever-increasing interest in modeling dynamic complex…

Data Structures and Algorithms · Computer Science 2015-09-18 Klaus Wehmuth , Artur Ziviani , Eric Fleury

Consider a graph $G=(V,E)$ without isolated edges and with maximum degree $\Delta$. Given a colouring $c:E\to\{1,2,\ldots,k\}$, the weighted degree of a vertex $v\in V$ is the sum of its incident colours, i.e., $\sum_{e\ni v}c(e)$. For any…

Combinatorics · Mathematics 2018-03-13 Jakub Przybyło

In this paper we provide some exact formulas for the regularity of powers of edge ideals of vertex-weighted oriented cycles and vertex-weighted unicyclic graphs. These formulas are functions of the weight of vertices and the number of…

Commutative Algebra · Mathematics 2019-04-05 Guangjun Zhu , Hong Wang , Li Xu , Jiaqi Zhang

We define the space of functions of bounded variation ($BV$) on the graph. Using the notion of divergence of flows on graphs, we show that the unit ball of the dual space to $BV$ in the graph setting can be described as the image of the…

Optimization and Control · Mathematics 2019-11-27 Japhet Niyobuhungiro , Eric Setterqvist , Freddie Åström , George Baravdish

Total Variation (TV) is a popular regularization strategy that promotes piece-wise constant signals by constraining the $\ell_1$-norm of the first order derivative of the estimated signal. The resulting optimization problem is usually…

Optimization and Control · Mathematics 2020-10-20 Hamza Cherkaoui , Jeremias Sulam , Thomas Moreau

A pair of graphs $(\Gamma,\Sigma)$ is called unstable if their direct product $\Gamma\times\Sigma$ admits automorphisms not from $\mathrm{Aut}(\Gamma)\times\mathrm{Aut}(\Sigma)$, and such automorphisms are said to be unexpected. The…

Combinatorics · Mathematics 2026-05-25 Xiaomeng Wang , Yan-Li Qin , Binzhou Xia

In this paper, we define and compare four new measures of graph irregularity. We use these measures to prove upper bounds for the chromatic number and the Colin de Verdiere parameter. We also strengthen the concise Turan theorem for…

Combinatorics · Mathematics 2014-11-05 Clive Elphick , Pawel Wocjan

If $\Gamma$ is a graph for which every edge is in exactly one clique of order $\omega$, then one can form a new graph with vertex set equal to these cliques. This is a generalization of the line graph of $\Gamma$. We discover many general…

Combinatorics · Mathematics 2026-05-25 Connor Phillips

Measures of the irregularity of chemical graphs could be helpful for QSAR/QSPR studies and for the descriptive purposes of biological and chemical properties, such as melting and boiling points, toxicity and resistance. Here we consider the…

Discrete Mathematics · Computer Science 2016-08-19 Hosam Abdo , Darko Dimitrov , Wei Gao

An $n$-vertex graph whose degree set consists of exactly $n-1$ elements is called antiregular graph. Such type of graphs are usually considered opposite to the regular graphs. An irregularity measure ($IM$) of a connected graph $G$ is a…

Combinatorics · Mathematics 2020-09-08 Akbar Ali , Tamás Réti

We investigate the \textit{group irregularity strength} ($s_g(G)$) of graphs, i.e. the smallest value of $s$ such that taking any Abelian group $\gr$ of order $s$, there exists a function $f:E(G)\rightarrow \gr$ such that the sums of edge…

Combinatorics · Mathematics 2017-12-01 Marcin Anholcer , Sylwia Cichacz

A proper total weighting of a graph $G$ is a mapping $\phi$ which assigns to each vertex and each edge of $G$ a real number as its weight so that for any edge $uv$ of $G$, $\sum_{e \in E(v)}\phi(e)+\phi(v) \ne \sum_{e \in…

Combinatorics · Mathematics 2017-05-24 Yu-Chang Liang , Tsai-Lien Wong , Xuding Zhu

This paper deals with the modular irregularity strength of a graph of n vertices, a new graph invariant, modified from the irregularity strength, by changing the condition of the vertex-weight set associate to the well-known irregular…

Combinatorics · Mathematics 2021-11-29 Meilin Imelda Tilukay

We investigate the \textit{group irregular strength} $(s_g(G))$ of graphs, i.e the smallest value of $s$ such that for any Abelian group $\Gamma$ of order $s$ exists a function $g\colon E(G) \rightarrow \Gamma$ such that sums of edge labels…

Combinatorics · Mathematics 2025-05-06 Sylwia Cichacz , Barbara Krupińska

In a recent work, we introduced a parametric framework for obtaining obstruction characterizations of graph parameters with respect to a quasi-ordering $\leqslant$ on graphs. Towards this, we proposed the concepts of class obstruction,…

Discrete Mathematics · Computer Science 2026-05-04 Christophe Paul , Evangelos Protopapas , Dimitrios M. Thilikos