Results 11 to 20 of about 945,213 (292)
The Shannon Capacity of Graph Powers
IEEE Transactions on Information TheoryFor a graph $G$, its $k$-th graph power $G^k$ is constructed by placing an edge between two vertices if they are within distance $k$. We consider the problem of deriving upper bounds on the Shannon capacity of graph powers by using spectral graph theory and linear optimization methods.
Aida Abiad +2 more
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The Behavior of Tree-Width and Path-Width Under Graph Operations and Graph Transformations
AlgorithmsTree-width and path-width are well-known graph parameters. Many NP-hard graph problems admit polynomial-time solutions when restricted to graphs of bounded tree-width or bounded path-width. In this work, we study the behavior of tree-width and path-width
Frank Gurski, Robin Weishaupt
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Cyclic labellings with constraints at two distances [PDF]
, 2004 Motivated by problems in radio channel assignment, we consider the vertex-labelling of graphs with non-negative integers. The objective is to minimise the span of the labelling, subject to constraints imposed at graph distances one and two.
Leese, R, Noble, S D
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Graph products of groups [PDF]
, 1990 In the 1970's Baudisch introduced the idea of the semifree group, that is, a group in which the only relators are commutators of generators. Baudisch was mainly concerned with subgroup problems, employing length arguments on the elements of these groups.
Green, E.R, Green, Elisabeth Ruth
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The Bounds for the First General Zagreb Index of a Graph
Universal Journal of Mathematics and Applications, 2021 The first general Zagreb index of a graph $G$ is defined as the sum of the $\alpha$th powers of the vertex degrees of $G$, where $\alpha$ is a real number such that $\alpha \neq 0$ and $\alpha \neq 1$.
Rao Li
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Permutational Powers of a Graph [PDF]
The Electronic Journal of Combinatorics, 2019 This paper introduces a new graph construction, the permutational power of a graph, whose adjacency matrix is obtained by the composition of a permutation matrix with the adjacency matrix of the graph. It is shown that this construction recovers the classical zig-zag product of graphs when the permutation is an involution, and it is in fact more ...
Matteo Cavaleri +2 more
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Forbidden Subgraphs of Power Graphs [PDF]
The Electronic Journal of Combinatorics, 2021 The undirected power graph (or simply power graph) of a group $G$, denoted by $P(G)$, is a graph whose vertices are the elements of the group $G$, in which two vertices $u$ and $v$ are connected by an edge between if and only if either $u=v^i$ or $v=u^j$ for some $i$, $j$.
Pallabi Manna +2 more
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Clustering Powers of Sparse Graphs [PDF]
The Electronic Journal of Combinatorics, 2020 We prove that if $G$ is a sparse graph — it belongs to a fixed class of bounded expansion $\mathcal{C}$ — and $d\in \mathbb{N}$ is fixed, then the $d$th power of $G$ can be partitioned into cliques so that contracting each of these clique to a single vertex again yields a sparse graph.
Nešetřil, Jaroslav +3 more
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On \delta^(k)-colouring of Powers of Paths and Cycles
Theory and Applications of Graphs, 2021 In a proper vertex colouring of a graph, the vertices are coloured in such a way that no two adjacent vertices receive the same colour, whereas in an improper vertex colouring, adjacent vertices are permitted to receive same colours subjected to some ...
Merlin Ellumkalayil, Sudev Naduvath
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Note on the Sum of Powers of Normalized Signless Laplacian Eigenvalues of Graphs [PDF]
Mathematics Interdisciplinary Research, 2019 In this paper, for a connected graph G and a real α≠0, we define a new graph invariant σα(G)-as the sum of the alphath powers of the normalized signless Laplacian eigenvalues of G.
Ş. Burcu Bozkurt Altındağ
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