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Recent evidence indicates that the abundance of recurring elementary interaction patterns in complex networks, often called subgraphs or motifs, carry significant information about their function and overall organization. Yet, the…

Disordered Systems and Neural Networks · Physics 2009-11-10 A. Vazquez , R. Dobrin , D. Sergi , J. -P. Eckmann , Z. N. Oltvai , A. -L. Barabasi

Sandpile groups are a subtle graph isomorphism invariant, in the form of a finite abelian group, whose cardinality is the number of spanning trees in the graph. We study their group structure for graphs obtained by attaching a cone vertex…

Combinatorics · Mathematics 2024-09-04 Victor Reiner , Dorian Smith

Understanding the structure of a graph along with the structure of its subgraphs is important for several problems in graph theory. Two examples are the Reconstruction Conjecture and isomorph-free generation. This paper raises the question…

Combinatorics · Mathematics 2009-09-18 Stephen G. Hartke , Hannah Kolb , Jared Nishikawa , Derrick Stolee

Knopfmacher et all [1] was introduced the graph compositions` notion. In this note we add to these a new construction of tree-like graphs where nodes are graphs themselves. The first examples of these tree-like compositions, a corresponding…

Combinatorics · Mathematics 2008-02-10 Wieslaw Bajguz

For a finitely generated free group F_n, of rank at least 2, any finite subgroup of Out(F_n) can be realized as a group of automorphisms of a graph with fundamental group F_n. This result, known as Out(F_n) realization, was proved by…

Group Theory · Mathematics 2007-05-23 Matt Clay

We give a general construction of topological groups from combinatorial structures such as trees, towers, gaps, and subadditive functions. We connect topological properties of corresponding groups with combinatorial properties of these…

General Topology · Mathematics 2025-06-24 Boriša Kuzeljević , Stepan Milošević , Stevo Todorčević

We present a mathematical framework for describing the topology of configuration spaces for particles on one-connected graphs. In particular, we compute the homology groups over integers for different classes of one-connected graphs. Our…

Mathematical Physics · Physics 2017-05-24 Tomasz Maciążek , Adam Sawicki

Group consensus implies reaching multiple groups where agents belonging to the same cluster reach state consensus. This paper focuses on linear multi-agent systems under nonnegative directed graphs. A new necessary and sufficient condition…

Systems and Control · Electrical Eng. & Systems 2021-11-16 Zhongchang Liu , Wing Shing Wong

The number of subgroups and the number of cyclic subgroups are natural combinatorial invariants of a finite group. We investigate how restrictions on these quantities, together with the number of distinct prime divisors of $|G|$, enforce…

Group Theory · Mathematics 2026-04-10 Angsuman Das , Hiranya Kishore Dey , Khyati Sharma

The monography examines the problem of constructing a group of automorphisms of a graph. A graph automorphism is a mapping of a set of vertices onto itself that preserves adjacency. The set of such automorphisms forms a vertex group of a…

History and Overview · Mathematics 2024-07-18 Sergey Kurapov , Maxim Davidovsky

There has been a great deal of attention recently to graphs whose vertex set is a group, defined using the group structure. (The commuting graph, where two elements are joined if they commute, is the oldest and most famous example.) The…

Combinatorics · Mathematics 2026-02-03 Peter J. Cameron

I define a "group graph" which encodes the symmetry in a dynamical process on a network. Group graphs extend signed networks, where links are labelled with plus or minus one, by allowing link labels from any group and generalising the…

Physics and Society · Physics 2025-07-18 Tim S. Evans

We prove a topological stability result for the actions of hyperbolic groups on their Bowditch boundaries. More precisely, we show that a sufficiently small perturbation of the standard boundary action, if assumed on each parabolic subgroup…

Group Theory · Mathematics 2025-09-16 Kathryn Mann , Jason Fox Manning , Theodore Weisman

Stanley introduced the concept of chromatic symmetric functions of graphs which extends and refines the notion of chromatic polynomials of graphs, and asked whether trees are determined up to isomorphism by their chromatic symmetric…

Combinatorics · Mathematics 2024-02-21 Yuzhenni Wang , Xingxing Yu , Xiao-Dong Zhang

This paper introduces a group-theoretic framework to analyze the algebraic structure of the Grover walk on a complete graph with self-loops. We construct a group generated by the Grover matrix and a diagonal matrix whose entries are powers…

Quantum Physics · Physics 2026-02-17 Tatsuya Tsurii , Naoharu Ito

We propose a generalisation of the congruence subgroup problem for groups acting on rooted trees. Instead of only comparing the profinite completion to that given by level stabilizers, we also compare pro-$\mathcal{C}$ completions of the…

Group Theory · Mathematics 2024-08-27 Alejandra Garrido , Jone Uria-Albizuri

We find the automorphism group of the moduli space of parabolic bundles on a smooth curve (with fixed determinant and system of weights). This group is generated by: automorphisms of the marked curve, tensoring with a line bundle, taking…

Algebraic Geometry · Mathematics 2023-03-03 David Alfaya , Tomas L. Gomez

The inducibility of a graph represents its maximum density as an induced subgraph over all possible sequences of graphs of size growing to infinity. This invariant of graphs has been extensively studied since its introduction in $1975$ by…

Optimization and Control · Mathematics 2025-12-19 Daniel Brosch , Diane Puges

Grouping the nodes of a graph into clusters is a standard technique for studying networks. We study a problem where we are given a directed network and are asked to partition the graph into a sequence of coherent groups. We assume that…

Social and Information Networks · Computer Science 2025-12-08 Iiro Kumpulainen , Nikolaj Tatti

We are concerned with orderable groups and particularly those with orderings invariant not only under multiplication, but also under a given automorphism or family of automorphisms. Several applications to topology are given: we prove that…

Group Theory · Mathematics 2014-10-01 Dale Rolfsen , Bert Wiest