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Related papers: Generalized Pell graphs

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Given a group G, the model $\mathcal{G}(G,p)$ denotes the probability space of all Cayley graphs of G where each element of the generating set is chosen independently at random with probability p. In this article we show that for any…

Combinatorics · Mathematics 2011-08-18 Demetres Christofides , Klas Markström

Recent research in graph pebbling has introduced the notion of a cover pebbling number. Along this same idea, we develop a more general pebbling function Pi(G, t, P). This measures the minimum number of pebbles needed to guarantee that any…

Combinatorics · Mathematics 2007-05-23 T. Ballie Arnold

We describe a new random greedy algorithm for generating regular graphs of high girth: Let $k\geq 3$ and $c \in (0,1)$ be fixed. Let $n \in \mathbb{N}$ be even and set $g = c \log_{k-1} (n)$. Begin with a Hamilton cycle $G$ on $n$ vertices.…

Combinatorics · Mathematics 2020-06-30 Nati Linial , Michael Simkin

An $(r,z,k)$-mixed graph $G$ has every vertex with undirected degree $r$, directed in- and out-degree $z$, and diameter $k$. In this paper, we study the case $r=z=1$, proposing some new constructions of $(1,1,k)$-mixed graphs with a large…

Combinatorics · Mathematics 2023-06-08 C. Dalfó , G. Erskine , G. Exoo , M. A. Fiol , N. López , A. Messegué , J. Tuite

Let $k \ge 2$ be an integer and consider the $k$-generalized Pell sequence $\{P_n^{(k)}\}_{n \ge 2-k}$, defined by the initial values $0, \ldots, 0, 0, 1$ (a total of $k$ terms), and the recurrence $P_n^{(k)} = 2P_{n-1}^{(k)} +…

Number Theory · Mathematics 2025-04-29 Herbert Batte

We introduce an iterative discrete information production process where we can extend ordered normalised vectors by new elements based on a simple affine transformation, while preserving the predefined level of inequality, G, as measured by…

Physics and Society · Physics 2024-01-17 Lucio Bertoli-Barsotti , Marek Gagolewski , Grzegorz Siudem , Barbara Żogała-Siudem

We consider sequences of the type $A_n=6A_{n-1}-A_{n-2}, A_0=r, A_1=s$ ($r$ and $s$ integers) and show that all sequences that solve particular cases of the Pell generalized equation are expressible as a constant times one of four…

Combinatorics · Mathematics 2007-05-23 Mario Catalani

Let $k$ and $l$ be integers, both at least 2. A $(k,l)$-bipartite graph is an $l$-regular bipartite multigraph with coloured bipartite sets of size $k$. Define $\chi(k,l)$ and $\mu(k,l)$ to be the minimum and maximum order of automorphism…

Combinatorics · Mathematics 2025-10-06 Peter J. Cameron , Coen del Valle , Colva M. Roney-Dougal

These are notes on the method of normalized graph cuts and its applications to graph clustering. I provide a fairly thorough treatment of this deeply original method due to Shi and Malik, including complete proofs. I include the necessary…

Computer Vision and Pattern Recognition · Computer Science 2013-11-12 Jean Gallier

Let $G$ be a nontrivial connected graph of order $n$, and $k$ an integer with $2\leq k\leq n$. For a set $S$ of $k$ vertices of $G$, let $\kappa (S)$ denote the maximum number $\ell$ of edge-disjoint trees $T_1,T_2,...,T_\ell$ in $G$ such…

Combinatorics · Mathematics 2010-12-30 Shasha Li , Wei Li , Xueliang Li

We prove a linear recurrence relation for a large family of generalized Schreier sets, which generalizes the Fibonacci recurrence proved by Bird and higher order Fibonacci recurrence proved by the second author et al. Furthermore, we show a…

Combinatorics · Mathematics 2022-01-03 Kevin Beanland , Hung Viet Chu , Carrie E. Finch-Smith

We give a complete characterization of graphs whose binomial edge ideal is licci. An important tool is a new general upper bound for the regularity of binomial edge ideals.

Commutative Algebra · Mathematics 2019-10-10 Viviana Ene , Giancarlo Rinaldo , Naoki Terai

A bipartite graph $G = (X \cup Y, E)$ is a 2-layer $k$-planar graph if it admits a drawing on the plane such that the vertices in $X$ and $Y$ are placed on two parallel lines respectively, edges are drawn as straight-line segments, and…

Discrete Mathematics · Computer Science 2026-02-20 Yuto Okada

To construct a Paley graph, we fix a finite field and consider its elements as vertices of the Paley graph. Two vertices are connected by an edge if their difference is a square in the field. We will study some important properties of the…

Combinatorics · Mathematics 2012-03-09 Ahmed Noubi Elsawy

The generalized $k$-edge-connectivity $\lambda_k(G)$ of a graph $G$ is a generalization of the concept of edge-connectivity. The lexicographic product of two graphs $G$ and $H$, denoted by $G\circ H$, is an important graph product. In this…

Combinatorics · Mathematics 2014-01-13 Xueliang Li , Jun Yue , Yan Zhao

We study a generalization of Pell's equation, whose coefficients are certain algebraic integers. Let $X_0=0$ and $X_n=\sqrt{2+X_{n-1}}$ for each $n\in \mathbb{Z}_{\ge 1}$. We study the $\mathbb{Z}[X_{n-1}]$-solutions of the equation…

Number Theory · Mathematics 2022-11-28 Hyuga Yoshizaki

A new generalization of Fiedler's lemma is obtained by introducing the concept of the main function of a matrix. As applications, the universal spectra of the H-join, the spectra of the H-generalized join and the spectra of the generalized…

Combinatorics · Mathematics 2020-08-31 M. Saravanan , S. P. Murugan , G. Arunkumar

A 2-cell embedding of a graph $G$ into a closed (orientable or nonorientable) surface is called regular if its automorphism group acts regularly on the flags - mutually incident vertex-edge-face triples. In this paper, we classify the…

Combinatorics · Mathematics 2010-01-19 Jin Ho Kwak , Young Soo Kwon

Following the spirit of a recent work of one of the authors (J. Phys. A: Math. Theor. 44 (2011) 045301), the essential structure of the generalized Pauli group of a qubit-qu$d$it, where $d = 2^{k}$ and an integer $k \geq 2$, is recast in…

Quantum Physics · Physics 2011-05-05 Metod Saniga , Michel Planat

A topological description of various generalized function algebras over corresponding basic locally convex algebras is given. The framework consists of algebras of sequences with appropriate ultra(pseudo)metrics defined by sequences of…

Functional Analysis · Mathematics 2019-04-01 Antoine Delcroix , Maximilian F. Hasler , Stevan Pilipović , Vincent Valmorin