Results 51 to 60 of about 382,145 (280)
On the Turán Properties of Infinite Graphs [PDF]
The Electronic Journal of Combinatorics, 2008 Let $G^{(\infty)}$ be an infinite graph with the vertex set corresponding to the set of positive integers ${\Bbb N}$. Denote by $G^{(l)}$ a subgraph of $G^{(\infty)}$ which is spanned by the vertices $\{1,\dots,l\}$. As a possible extension of Turán's theorem to infinite graphs, in this paper we will examine how large $\liminf_{l\rightarrow \infty} {|
Andrzej Dudek, Vojtech Rödl
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A Structured Inverse Spectrum Problem for Infinite Graphs and Unbounded Operators
, 2017 Given an infinite graph $G$ on countably many vertices, and a closed, infinite set $\Lambda$ of real numbers, we prove the existence of an unbounded self-adjoint operator whose graph is $G$ and whose spectrum is $\Lambda$
Khanmohammadi, Ehssan
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Cycle Double Covers of Infinite Planar Graphs
Discussiones Mathematicae Graph Theory, 2016 In this paper, we study the existence of cycle double covers for infinite planar graphs. We show that every infinite locally finite bridgeless k-indivisible graph with a 2-basis admits a cycle double cover.
Javaheri Mohammad
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On the Structure of a Triangle-Free Infinite-Chromatic Graph of Gyarfas
International Journal of Mathematics and Mathematical Sciences, 1983 Gyárfás has recently constructed an elegant new example of a triangle-free infinite graph G with infinite chromatic number. We analyze its structure by studying the properties of a nested family of subgraphs Gn whose union is G.
Larry Eggan, Frank Harary
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The center of an infinite graph
Discrete Mathematics, 1996 In this note we extend the notion of the center of a graph to infinite graphs. Thus, a vertex is in the center of the infinite graph G if it is in the center of an increasing family of finite subgraphs covering G. We give different characterizations of when a vertex is in the center of an infinite graph and we prove that any infinite graph with at ...
Boza Prieto, Luis +2 more
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A notion of graph likelihood and an infinite monkey theorem
, 2013 We play with a graph-theoretic analogue of the folklore infinite monkey theorem. We define a notion of graph likelihood as the probability that a given graph is constructed by a monkey in a number of time steps equal to the number of vertices. We present
Banerji, Christopher R. S. +2 more
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An advance in infinite graph models for the analysis of transportation networks
International Journal of Applied Mathematics and Computer Science, 2016 This paper extends to infinite graphs the most general extremal issues, which are problems of determining the maximum number of edges of a graph not containing a given subgraph.
Cera Martín, Fedriani Eugenio M.
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Finite Voronoi decompositions of infinite vertex transitive graphs
, 2011 In this paper, we consider the Voronoi decompositions of an arbitrary infinite vertex-transitive graph G. In particular, we are interested in the following question: what is the largest number of Voronoi cells that must be infinite, given sufficiently ...
Borsuk K., HILARY FINUCANE
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Nonplanarity of Iterated Line Graphs
Journal of Mathematics, 2020 The 1-crossing index of a graph G is the smallest integer k such that the kth iterated line graph of G has crossing number greater than 1. In this paper, we show that the 1-crossing index of a graph is either infinite or it is at most 5.
Jing Wang
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SMT Solving for Functional Programming over Infinite Structures [PDF]
Electronic Proceedings in Theoretical Computer Science, 2016 We develop a simple functional programming language aimed at manipulating infinite, but first-order definable structures, such as the countably infinite clique graph or the set of all intervals with rational endpoints.
Bartek Klin, Michał Szynwelski
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