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Related papers: Bipartite Rigidity

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Consider the random process in which the edges of a graph $G$ are added one by one in a random order. A classical result states that if $G$ is the complete graph $K_{2n}$ or the complete bipartite graph $K_{n,n}$, then typically a perfect…

Combinatorics · Mathematics 2020-11-03 Roman Glebov , Zur Luria , Michael Simkin

In this paper, we identify two fractals if and only if they are biLipschitz equivalent. Fix ratio $r,$ for dust-like graph-directed sets with ratio $r$ and integer characteristics, we show that they are rigid in the sense that they are…

Metric Geometry · Mathematics 2013-08-15 Li-Feng Xi , Ying Xiong

We strengthen a result by Laskar and Lyle (Discrete Appl. Math. (2009), 330-338) by proving that it is NP-complete to decide whether a bipartite planar graph can be partitioned into three independent dominating sets. In contrast, we show…

Computational Complexity · Computer Science 2019-05-14 Juho Lauri , Christodoulos Mitillos

For integer $k\geq2$ and prime power $q$, the algebraic bipartite graph $D(k,q)$ proposed by Lazebnik and Ustimenko (1995) is meaningful not only in extremal graph theory but also in coding theory and cryptography. This graph is…

Combinatorics · Mathematics 2022-07-27 Ming Xu , Xiaoyan Cheng , Yuansheng Tang

We determine the colored patterns that appear in any $2$-edge coloring of $K_{n,n}$, with $n$ large enough and with sufficient edges in each color. We prove the existence of a positive integer $z_2$ such that any $2$-edge coloring of…

Combinatorics · Mathematics 2024-07-15 Adriana Hansberg , Denae Ventura

We say that a bipartite graph $G(A, B)$ with fixed parts $A$, $B$ is proximinal if there is a semimetric space $(X, d)$ such that $A$ and $B$ are disjoint proximinal subsets of $X$ and all edges $\{a, b\}$ satisfy the equality $d(a, b) =…

Combinatorics · Mathematics 2022-01-24 Karim Chaira , Oleksiy Dovgoshey , Samih Lazaiz

Let $t$ be a positive real number. A graph is called $t$-tough if the removal of any vertex set $S$ that disconnects the graph leaves at most $|S|/t$ components. The toughness of a graph is the largest $t$ for which the graph is $t$-tough.…

Discrete Mathematics · Computer Science 2019-10-22 Gyula Y Katona , Kitti Varga

This paper studies $k$-claw-free graphs, exploring the connection between an extremal combinatorics question and the power of a convex program in approximating the maximum-weight independent set in this graph class. For the extremal…

Computational Complexity · Computer Science 2023-08-31 Parinya Chalermsook , Ameet Gadekar , Kamyar Khodamoradi , Joachim Spoerhase

The Erd\H{o}s-Simonovits stability theorem states that for all \epsilon >0 there exists \alpha >0 such that if G is a K_{r+1}-free graph on n vertices with e(G) > ex(n,K_{r+1}) - \alpha n^2, then one can remove \epsilon n^2 edges from G to…

Combinatorics · Mathematics 2022-05-03 József Balogh , Felix Christian Clemen , Mikhail Lavrov , Bernard Lidický , Florian Pfender

Sidorenko's conjecture states that the number of copies of any given bipartite graph in another graph of given density is asymptotically minimized by a random graph. The forcing conjecture further strengthens this, claiming that any…

Combinatorics · Mathematics 2024-12-18 Aldo Kiem , Olaf Parczyk , Christoph Spiegel

A theorem of Nosal and Nikiforov states that if $G$ is a triangle-free graph with $m$ edges, then $\lambda (G)\le \sqrt{m}$, where the equality holds if and only if $G$ is a complete bipartite graph. A well-known spectral conjecture of…

Combinatorics · Mathematics 2024-03-13 Yongtao Li , Lihua Feng , Yuejian Peng

Beyond-planarity focuses on the study of geometric and topological graphs that are in some sense nearly-planar. Here, planarity is relaxed by allowing edge crossings, but only with respect to some local forbidden crossing configurations.…

Discrete Mathematics · Computer Science 2017-12-29 Patrizio Angelini , Michael A. Bekos , Michael Kaufmann , Maximilian Pfister , Torsten Ueckerdt

Bipartite graphs are a fundamental concept in graph theory with diverse applications. A graph is bipartite iff it contains no odd cycles, a characteristic that has many implications in diverse fields ranging from matching problems to the…

Combinatorics · Mathematics 2024-12-10 Marzieh Eidi , Sayan Mukherjee

In this paper, we investigate odd graceful graph, odd strongly harmonious graph, bipartite graph and their relationship. We proved following results: (1) if G is odd strongly harmonious graph, then G is odd graceful graph ;(2) if G is…

Combinatorics · Mathematics 2020-01-06 Xiuying Wang , Ying Zhoua , Haihong Wanga , Chunfeng Liu

Consider a graph with $n$ vertices where the shortest odd cycle is of length $>2k+1$. We revisit two known results about such graphs: (I) Such a graph is almost bipartite, in the sense that it can be made bipartite by removing from it…

Discrete Mathematics · Computer Science 2018-10-05 Sariel Har-Peled , Saladi Rahul

The conjecture of Bollob\'as and Koml\'os, recently proved by B\"ottcher, Schacht, and Taraz [Math. Ann. 343(1), 175--205, 2009], implies that for any $\gamma>0$, every balanced bipartite graph on $2n$ vertices with bounded degree and…

Combinatorics · Mathematics 2011-07-28 Julia Böttcher , Peter Christian Heinig , Anusch Taraz

How does one determine if a collection of bars joined by freely rotating hinges cannot be deformed without changing the length of any of the bars? In other words, how does one determine if a bar-joint graph is rigid? This question has been…

Disordered Systems and Neural Networks · Physics 2024-10-02 Kyungeun Kim , J. M. Schwarz

Let $k,p,q$ be three positive integers. A graph $G$ with order $n$ is said to be $k$-placeable if there are $k$ edge disjoint copies of $G$ in the complete graph on $n$ vertices. A $(p,\,q)$-graph is a graph of order $p$ with $q$ edges.…

Combinatorics · Mathematics 2020-12-14 Yun Wang , Jin Yan

We study the problem of Minimum $k$-Critical Bipartite Graph of order $(n,m)$ - M$k$CBG-$(n,m)$: to find a bipartite $G=(U,V;E)$, with $|U|=n$, $|V|=m$, and $n>m>1$, which is $k$-critical bipartite, and the tuple $(|E|, \Delta_U,…

Combinatorics · Mathematics 2021-09-06 Sylwia Cichacz , Karol Suchan

Mixed graphs can be seen as digraphs with arcs and edges (or digons, that is, two opposite arcs). In this paper, we consider the case where such graphs are bipartite and in which the undirected and directed degrees are one. The best graphs,…

Combinatorics · Mathematics 2024-03-29 C. Dalfó , G. Erskine , G. Exoo , M. A. Fiol , J. Tuite