Results 11 to 20 of about 88,228 (240)
Combinatorics of Nahm sums, quiver resultants and the K-theoretic condition
Journal of High Energy Physics, 2021 Algebraic Nahm equations, considered in the paper, are polynomial equations, governing the q → 1 limit of the q-hypergeometric Nahm sums. They make an appearance in various fields: hyperbolic geometry, knot theory, quiver representation theory ...
Dmitry Noshchenko
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Wiener index and addressing of some finite graphs
AKCE International Journal of Graphs and Combinatorics, 2023 An addressing of length t of a graph G is an assignment of t-tuples with entries in [Formula: see text] called addresses, to the vertices of G such that the distance between any two vertices can be determined from their addresses.
Mona Gholamnia Taleshani, Ahmad Abbasi
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A Note on Some Bounds of the α-Estrada Index of Graphs
Advances in Mathematical Physics, 2020 Let G be a simple graph with n vertices. Let A~αG=αDG+1−αAG, where 0≤α≤1 and AG and DG denote the adjacency matrix and degree matrix of G, respectively. EEαG=∑i=1neλi is called the α-Estrada index of G, where λ1,⋯,λn denote the eigenvalues of A~αG.
Yang Yang, Lizhu Sun, Changjiang Bu
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On the adjacency matrix of a complex unit gain graph [PDF]
Linear and multilinear algebra, 2018 A complex unit gain graph is a simple graph in which each orientation of an edge is given a complex number with modulus 1 and its inverse is assigned to the opposite orientation of the edge.
Ranjit Mehatari +2 more
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New Bounds for the α-Indices of Graphs
Mathematics, 2020 Let G be a graph, for any real 0≤α≤1, Nikiforov defines the matrix Aα(G) as Aα(G)=αD(G)+(1−α)A(G), where A(G) and D(G) are the adjacency matrix and diagonal matrix of degrees of the vertices of G.
Eber Lenes +2 more
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On the Aα-Eigenvalues of Signed Graphs
Mathematics, 2021 For α∈[0,1], let Aα(Gσ)=αD(G)+(1−α)A(Gσ), where G is a simple undirected graph, D(G) is the diagonal matrix of its vertex degrees and A(Gσ) is the adjacency matrix of the signed graph Gσ whose underlying graph is G.
Germain Pastén, Oscar Rojo, Luis Medina
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Aα-Spectral Characterizations of Some Joins
Journal of Mathematics, 2020 Let G be a graph with n vertices. For every real α∈0,1, write AαG for the matrix AαG=αDG+1−αAG, where AG and DG denote the adjacency matrix and the degree matrix of G, respectively.
Tingzeng Wu, Tian Zhou
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Graphs Whose Aα -Spectral Radius Does Not Exceed 2
Discussiones Mathematicae Graph Theory, 2020 Let A(G) and D(G) be the adjacency matrix and the degree matrix of a graph G, respectively. For any real α ∈ [0, 1], we consider Aα (G) = αD(G) + (1 − α)A(G) as a graph matrix, whose largest eigenvalue is called the Aα -spectral radius of G.
Wang Jian Feng +3 more
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Directed random geometric graphs: structural and spectral properties
Journal of Physics: Complexity, 2022 In this work we analyze structural and spectral properties of a model of directed random geometric graphs: given n vertices uniformly and independently distributed on the unit square, a directed edge is set between two vertices if their distance is ...
Kevin Peralta-Martinez +1 more
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Characteristic polynomial of anti-adjacency matrix of directed cyclic friendship graph
Journal of Physics: Conference Series, 2020 Graph theory has some applications. One of them is used to do social network analysis as in Facebook with each person as nodes and every like, share, comment, tag as edges. Usually a network can be represented by a graph.
N. Anzana +3 more
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