搜索结果: 1-15 共查到“代数学 graphs”相关记录32条 . 查询时间(0.109 秒)
Growing well-connected graphs
The algebraic connectivity graph Laplacian characteristic values of semidefinite programming calculation vector
2015/8/10
The algebraic connectivity of a graph is the second smallest eigenvalue of the graph Laplacian, and is a measure of how well connected the graph is. We study the problem of adding edges (from a set of...
We develop a nonlinear spectral graph theory, in which the Laplace
operator is replaced by the 1 Laplacian ∆1
. The eigenvalue problem is to
solve a nonlinear system, involving a set valued f...
Kac's Theorem for equipped graphs and for maximal rank representations
Kac's Theorem maximal rank representations Representation Theory
2011/9/22
Abstract: We give two generalizations of Kac's Theorem on representations of quivers. One is to representations of equipped graphs by relations, in the sense of Gelfand and Ponomarev. The other is to ...
The incidence Hopf algebra of graphs
combinatorial Hopf algebra graph chromatic polynomial
2011/2/24
The graph algebra is a commutative, cocommutative, graded,connected incidence Hopf algebra, whose basis elements correspond to fi-nite simple graphs and whose Hopf product and coproduct admit simple c...
Tricyclic graphs with exactly two main eigenvalues
Main eigenvalues Tricyclic graphs 2-walk (a, b)-linear graphs
2011/1/18
An eigenvalue of a graph G is called a main eigenvalue if it has an eigenvector the sum of whose entries is not equal to zero. In this paper, all connected tricyclic graphs with exactly two main eigen...
Exponentially many perfect matchings in cubic graphs
Exponentially many perfect matchings cubic graphs
2011/1/21
We show that every cubic bridgeless graph G has at least 2|V (G)|/3656 perfect matchings.
This confirms an old conjecture of Lov´asz and Plummer.
Minimizing Laplacian spectral radius of unicyclic graphs with fixed girth
Laplacian matrix Laplacian spectral radius girth unicyclic graph
2011/1/18
In this paper we consider the following problem: Over the class of all simple con-nected unicyclic graphs on n vertices with girth g (n, g being fixed), which graph minimizes the Laplacian spectral ra...
We present the program boundary, whose source les are available at http://people.sissa.it/~maggiolo/boundary/. Given two natural num-bers g and n satisfying 2g + n 2 > 0, the program gener...
In this paper we study zero-divisor graphs of semirings. We show that all zero-divisor graphs of (possibly noncommutative) semirings are connected and have diameter less than or equal to 3. We charact...
Abelian JSJ decomposition of graphs of free abelian groups
Abelian JSJ decomposition graphs of free abelian groups
2011/1/19
A group G is a vGBS group if it admits a decomposition as a fi-nite graph of groups with all edge and vertex groups finitely generated and free abelian. We construct the JSJ decomposition of a vGBS gr...
We consider the graph together with the arbitrary partition of its vertex set into n subsets (n-partitioned graph). On the set of $n$-partitioned graphs distinguished up to isomorphism we define the b...
Complete solution to a conjecture on the maximal energy of unicyclic graphs
Complete solution conjecture unicyclic graphs
2010/11/24
For a given simple graph $G$, the energy of $G$ denoted by $E(G)$, is defined as the sum of the absolute values of all eigenvalues of its adjacency matrix. Let $P_n^{\ell}$ be the unicyclic graph obt...
A path in an edge-colored graph, where adjacent edges may be colored the same, is a rainbow path if no two edges of it are colored the same. A nontrivial connected graph $G$ is rainbow connected if th...
In this paper we consider a model for the spread of a stochastic SIR (Susceptible $\to$ Infectious $\to$ Removed) epidemic on a network of individuals described by a random intersection graph. The nu...
Moving closer: contractive maps on discrete metric spaces and graphs
Moving closer discrete metric spaces and graphs
2010/11/23
We consider discrete metric spaces and we look for non-constant contractions. We introduce the notion of contractive map and we characterize the spaces with non-constant contractive maps. We provide s...