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Related papers: Ramanujan Graphs

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We enumerate graph homomorphisms to quasi-complete graphs, i.e., graphs obtained from complete graphs by removing one edge. The source graphs are complete graphs, quasi-complete graphs, cycles, paths, wheels and broken wheels. These…

Combinatorics · Mathematics 2016-01-26 Pedro Lopes

In this paper, we introduce the notion of a finite non-simple directed graph, called an ornated graph and initiate a study on ornated graphs. An ornated graph is a directed graph on $n$ vertices, denoted by $O_n(s_l)$, whose vertices are…

Combinatorics · Mathematics 2015-05-29 Johan Kok , Sudev Naduvath , Vivian Mukungunugwa

Graph neural networks (GNNs) have attracted much attention due to their ability to leverage the intrinsic geometries of the underlying data. Although many different types of GNN models have been developed, with many benchmarking procedures…

We provide an annotated bibliography for the study of Hamilton cycles in random graphs and hypergraphs.

Combinatorics · Mathematics 2025-06-26 Alan Frieze

We provide a comprehensive review of the existing literature on memory-augmented GNNs. We review these works through the lens of psychology and neuroscience, which has several established theories on how multiple memory systems and…

Machine Learning · Computer Science 2023-07-18 Guixiang Ma , Vy A. Vo , Theodore Willke , Nesreen K. Ahmed

This survey paper aims at providing a "literary" anthology of mathematical morphology on graphs. It describes in the English language many ideas stemming from a large number of different papers, hence providing a unified view of an active…

Computer Vision and Pattern Recognition · Computer Science 2014-09-29 Laurent Najman , Jean Cousty

This paper uses the theory of covering graphs to characterize some of the edge-transitive graphs which can arise as token graphs.

Combinatorics · Mathematics 2025-05-28 Sergio G. Gómez-Galicia , Octavio B. Zapata-Fonseca

In the present work we are going to give a formal exposition of the ribbon graphs topic based on notes of Labourie \cite{Lab}, since is difficult to find as such in the literature.

Combinatorics · Mathematics 2017-04-26 Rodrigo Dávila Figueroa

Inspired by the recent pioneering work, dubbed "The Ramanujan Machine" by Raayoni et al. (arXiv:1907.00205), we (automatically) [rigorously] prove some of their conjectures regarding the exact values of some specific infinite continued…

Number Theory · Mathematics 2020-05-27 Robert Dougherty-Bliss , Doron Zeilberger

In this paper we introduce the quadratic Jaco graph. The characteristics, properties and some graph invariants of quadratic Jaco graphs are discussed. The observation that quadratic Jaco graphs are well-defined in respect of complete graphs…

General Mathematics · Mathematics 2016-09-13 R. Jayasree , A. Kulandai Therese , U. Mary , Johan Kok

The symmetric tensor power of graphs is introduced and its fundamental properties are explored. A wide range of intriguing phenomena occur when one considers symmetric tensor powers of familiar graphs. A host of open questions are…

In their seminal paper, Lubotzky, Phillips and Sarnak (LPS) defined the notion of regular Ramanujan graphs and gave an explicit construction of infinite families of $(p+1)$-regular Ramanujan Cayley graphs, for infinitely many primes $p$. In…

Number Theory · Mathematics 2026-04-08 Shai Evra , Brooke Feigon , Kathrin Maurischat , Ori Parzanchevski

Using the WZ-method we find some of the easiest Ramanujan's formulae and also some new interesting Ramanujan-like sums.

Number Theory · Mathematics 2007-05-23 Jesus Guillera

We raise some questions about graph polynomials, highlighting concepts and phenomena that may merit consideration in the development of a general theory. Our questions are mainly of three types: When do graph polynomials have reduction…

Combinatorics · Mathematics 2024-06-25 Graham Farr , Kerri Morgan

In this short note, we give a description of the Parry-Sullivan number of a graph in terms of the cycles in the graph. This tool is occasionally useful in reasoning about the Parry-Sullivan numbers of graphs.

Combinatorics · Mathematics 2009-03-12 Chris Smith

Graph Neural Networks (GNNs), neural network architectures targeted to learning representations of graphs, have become a popular learning model for prediction tasks on nodes, graphs and configurations of points, with wide success in…

Machine Learning · Computer Science 2022-04-19 Stefanie Jegelka

Comparability graphs are a popular class of graphs. We introduce as the digraph analogue of comparability graphs the class of comparability digraphs. We show that many concepts such as implication classes and the knotting graph for a…

Combinatorics · Mathematics 2022-04-05 Xiao-Lu Gao , Jing Huang , Shou-Jun Xu

The concept of graph powers has been extensively studied in graph theory. Analogous to graph powers, Chandran et al. [3] introduced the notion of bipartite powers for bipartite graphs. In this paper, we show that the class of interval…

Combinatorics · Mathematics 2025-09-29 Indrajit Paul , Ashok Kumar Das

In this paper we discuss reconstruction problems for graphs. We develop some new ideas like isomorphic extension of isomorphic graphs, partitioning of vertex sets into sets of equivalent points, subdeck property, etc. and develop an…

General Mathematics · Mathematics 2011-10-21 Dhananjay P. Mehendale

We examine a method to conjecture two very famous identities that were conjectured by Ramanujan, and later found to be known to Rogers.

Classical Analysis and ODEs · Mathematics 2016-09-20 Gaurav Bhatnagar