Results 11 to 20 of about 728,663 (278)
Laplacian spectral determination of path-friendship graphs [PDF]
AKCE International Journal of Graphs and Combinatorics, 2021 A graph G is said to be determined by the spectrum of its Laplacian matrix (DLS) if every graph with the same spectrum is isomorphic to G. In some recent papers it is proved that the friendship graphs and starlike trees are DLS. If a friendship graph and
Mohammad Reza Oboudi +3 more
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Interlace polynomials of friendship graphs [PDF]
Electronic Journal of Graph Theory and Applications, 2018 In this paper, we study the interlace polynomials of friendship graphs, that is, graphs that satisfy the Friendship Theorem given by Erdös, Rényi and Sos.
Christina Eubanks-Turner, Aihua Li
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Graphs cospectral with a friendship graph or its complement [PDF]
Transactions on Combinatorics, 2013 Let $n$ be any positive integer and let $F_n$ be the friendship (or Dutch windmill) graph with $2n+1$ vertices and $3n$ edges. Here we study graphs with the same adjacency spectrum as the $F_n$.
Alireza Abdollahi +2 more
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Connected graphs cospectral with a Friendship graph [PDF]
Transactions on Combinatorics, 2014 Let $n$ be any positive integer, the friendship graph $F_n$ consists of $n$ edge-disjoint triangles that all of them meeting in one vertex. A graph $G$ is called cospectral with a graph $H$ if their adjacency matrices have the same eigenvalues.
Alireza Abdollahi , Shahrooz Janbaz
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On Strongly Regular Graphs and the Friendship Theorem
MathematicsThis paper presents an alternative proof of the celebrated friendship theorem, originally established by Erdős, Rényi, and Sós in 1966. The proof relies on a closed-form expression for the Lovász ϑ-function of strongly regular graphs, recently derived by
Igal Sason
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The eccentricity spread of weak-friendship graphs [PDF]
Discrete Mathematics Letters, 2023 Summary: A weak-friendship graph is a connected induced subgraph of a friendship graph. The unique graphs attaining the first two smallest eccentricity spread in the class of weak-friendship graphs of given order are determined in this paper.
Jia X., Li X., Brunetti M.
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The Complexity of Octopus Graph, Friendship Graph, and Snail Graph [PDF]
EduMatSains : Jurnal Pendidikan, Matematika dan SainsGraphs are basic structures that represent objects with nodes and relationships between objects with edges. Trees are one of the parts studied in graph theory along with finding the number of spanning trees of a graph such as octopus graph, friendship graph, and snail graph.
Fransiskus Fran +4 more
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Degrees of Vertices in a Friendship Graph
Canadian Mathematical Bulletin, 1975 AbstractA friendship graph is a graph in which every two distinct vertices have exactly one common adjacent vertex (called a neighbour). Finite friendship graphs have been characterized by Erdós, Rényi and Sós [2]: Each finite friendship graph Fn which consists of n edge disjoint triangles such that all n>1 triangles have one vertex in common (F1 is
Anton Kotzig
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A sum labelling for the generalised friendship graph
Discrete Mathematics, 2008 zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Henning Fernau +2 more
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Friendship Decompositions of Graphs: The general problem
Open Journal of Applied Sciences, 2012 A friendship graph is a graph consisting of cliques sharing a common vertex. In this paper we investigate the maximum number of elements in an optimal friendship decomposition of graphs of order n. We obtain upper and lower bounds for this number. These bounds relate this problem with the classical Ramsey numbers.
Teresa Sousa
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