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Related papers: On Clique Graphs and Clique Regular Graphs

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We extend the clique-coclique inequality, previously known to hold for graphs in association schemes and vertex-transitive graphs, to graphs in homogeneous coherent configurations and 1-walk regular graphs. We further generalize it to a…

Combinatorics · Mathematics 2019-10-15 Marcel K. de Carli Silva , Gabriel Coutinho , Chris Godsil , David E. Roberson

We consider the problem of finding a large clique in an Erd\H{o}s--R\'enyi random graph where we are allowed unbounded computational time but can only query a limited number of edges. Recall that the largest clique in $G \sim G(n,1/2)$ has…

Combinatorics · Mathematics 2024-07-12 Endre Csóka , András Pongrácz

Clique-width is a well-studied graph parameter. For graphs of bounded clique-width, many problems that are NP-hard in general can be polynomial-time solvable. The fact motivates several studies to investigate whether the clique-width of…

Data Structures and Algorithms · Computer Science 2022-02-01 Yu Nakahata

A strong clique in a graph is a clique intersecting every maximal independent set. We study the computational complexity of six algorithmic decision problems related to strong cliques in graphs and almost completely determine their…

Combinatorics · Mathematics 2018-08-28 Ademir Hujdurović , Martin Milanič , Bernard Ries

The problem of maximising the number of cliques among $n$-vertex graphs from various graph classes has received considerable attention. We investigate this problem for the class of $1$-planar graphs where we determine precisely the maximum…

Combinatorics · Mathematics 2021-09-08 J. Pascal Gollin , Kevin Hendrey , Abhishek Methuku , Casey Tompkins , Xin Zhang

A bound on consecutive clique numbers of graphs is established. This bound is evaluated and shown to often be much better than the bound of the Kruskal-Katona theorem. A bound on non-consecutive clique numbers is also proven.

Combinatorics · Mathematics 2007-10-23 Andy Frohmader

We study some percolation problems on the complete graph over $\mathbf N$. In particular, we give sharp sufficient conditions for the existence of (finite or infinite) cliques and paths in a random subgraph. No specific assumption on the…

Probability · Mathematics 2011-03-29 A. Berarducci , P. Majer , M. Novaga

In this paper, we study the order of a maximal clique in an amply regular graph with a fixed smallest eigenvalue by considering a vertex that is adjacent to some (but not all) vertices of the maximal clique. As a consequence, we show that…

Combinatorics · Mathematics 2020-12-18 Gary R. W. Greaves , Jack H. Koolen , Jongyook Park

This paper proposes a new algorithm for solving maximal cliques for simple undirected graphs using the theory of prime numbers. A novel approach using prime numbers is used to find cliques and ends with a discussion of the algorithm.

Data Structures and Algorithms · Computer Science 2007-05-23 Dhananjay D. Kulkarni , Shekhar Verma , Prashant

It is shown how to construct a clique graph in which properties of cliques of a fixed order in a given graph are represented by vertices in a weighted graph. Various definitions and motivations for these weights are given. The detection of…

Physics and Society · Physics 2011-01-04 T. S. Evans

We give a uniform and self-contained proof that if $G$ is a connected graph with $\chi(G) = \Delta(G)$ and $G\neq \overline{C_7}$, then $G$ contains either $K_{\Delta(G)}$ or an odd hole where every vertex has degree at least $\Delta(G)-1$…

Combinatorics · Mathematics 2025-08-14 Rachel Galindo , Jessica McDonald , Songling Shan

Let $G$ be a graph and $\mathcal{K}_G$ be the set of all cliques of $G$, then the clique graph of G denoted by $K(G)$ is the graph with vertex set $\mathcal{K}_G$ and two elements $Q_i,Q_j \in \mathcal{K}_G$ form an edge if and only if $Q_i…

Combinatorics · Mathematics 2015-08-18 S. M. Hegde , V. V. P. R. V. B. Suresh Dara

A \emph{clique} is a set of pairwise adjacent vertices in a graph. We determine the maximum number of cliques in a graph for the following graph classes: (1) graphs with $n$ vertices and $m$ edges; (2) graphs with $n$ vertices, $m$ edges,…

Combinatorics · Mathematics 2010-06-17 David R. Wood

The theory of dense graph limits comes with a natural sampling process which yields an inhomogeneous variant G(n,W) of the Erdos-Renyi random graph. Here we study the clique number of these random graphs. We establish the concentration of…

Combinatorics · Mathematics 2018-12-04 Martin Doležal , Jan Hladký , András Máthé

In a network cliques are fully connected subgraphs that reveal which are the tight communities present in it. Cliques of size c>3 are present in random Erdos and Renyi graphs only in the limit of diverging average connectivity. Starting…

Disordered Systems and Neural Networks · Physics 2009-11-11 Ginestra Bianconi , Matteo Marsili

A regular clique in a regular graph is a clique such that every vertex outside of the clique is adjacent to the same positive number of vertices inside the clique. We continue the study of regular cliques in edge-regular graphs initiated by…

Combinatorics · Mathematics 2021-03-02 Rhys J. Evans , Sergey Goryainov , Dmitry Panasenko

Let $G$ be a non-abelian group. The non-commuting graph $\mathcal{A}_G$ of $G$ is defined as the graph whose vertex set is the non-central elements of $G$ and two vertices are joint if and only if they do not commute. In a finite simple…

Group Theory · Mathematics 2009-03-05 A. Abdollahi , A. Azad , A. Mohammadi Hassanabadi , M. Zarrin

The definition of edge-regularity in graphs is a relaxation of the definition of strong regularity, so strongly regular graphs are edge-regular and, not surprisingly, the family of edge-regular graphs is much larger and more diverse than…

Combinatorics · Mathematics 2025-04-14 Jared DeLeo

Large graphs are sometimes studied through their degree sequences (power law or regular graphs). We study graphs that are uniformly chosen with a given degree sequence. Under mild conditions, it is shown that sequences of such graphs have…

Probability · Mathematics 2011-08-31 Sourav Chatterjee , Persi Diaconis , Allan Sly

A Neumaier graph is a non-complete edge-regular graph containing a regular clique. A Neumaier graph that is not strongly regular is called a strictly Neumaier graph. In this work we present a new construction of strictly Neumaier graphs,…

Combinatorics · Mathematics 2021-09-30 Aida Abiad , Wouter Castryck , Maarten De Boeck , Jack H. Koolen , Sjanne Zeijlemaker