Results 1 to 10 of about 742 (250)
Information Inequalities via Submodularity and a Problem in Extremal Graph Theory [PDF]
The present paper offers, in its first part, a unified approach for the derivation of families of inequalities for set functions which satisfy sub/supermodularity properties.
Igal Sason
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Extremal infinite graph theory
We survey various aspects of infinite extremal graph theory and prove several new results. The lead role play the parameters connectivity and degree. This includes the end degree. Many open problems are suggested.
Maya Stein
exaly +5 more sources
Extremal graph theory and finite forcibility [PDF]
We study the uniqueness of optimal solutions to extremal graph theory problems. Our main result is a counterexample to the following conjecture of Lov´asz, which is often referred to as saying that “every extremal graph theory problem has a finitely forcible optimum”: every finite feasible set of subgraph density constraints can be extended further by ...
Andrzej Grzesik +2 more
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Extremal Graph Theory for Metric Dimension and Diameter [PDF]
A set of vertices $S$ resolves a connected graph $G$ if every vertex is uniquely determined by its vector of distances to the vertices in $S$. The metric dimension of $G$ is the minimum cardinality of a resolving set of $G$. Let ${\cal G}_{\beta,D}$ be the set of graphs with metric dimension $\beta$ and diameter $D$.
CARLOS Seara +2 more
exaly +6 more sources
On new results on extremal graph theory, theory of algebraic graphs, and their applications
New explicit constructions of infinite families of finite small world graphs of large girth with well-defined projective limits which is an infinite tree are described.
V.O. Ustimenko
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On an extremal problem in graph theory [PDF]
Let \(l\) and \(p\) be integers such that \(l>p\). It is shown that there exists a constant \(\gamma_{p,l}\) such that if \(n>n_0(p,l)\) then every graph with \(n\) vertices and \([\gamma_{p,l}n^{2-1/p}]\) edges contains a subgraph \(H\) with the following property: the vertices of \(H\) may be labbeled \(x_1,...,x_l\) and \(y_1,...,y_l\) so that every
exaly +3 more sources
It Is Better to Be Semi-Regular When You Have a Low Degree [PDF]
We study the algebraic connectivity for several classes of random semi-regular graphs. For large random semi-regular bipartite graphs, we explicitly compute both their algebraic connectivity as well as the full spectrum distribution. For an integer d∈3,7,
Theodore Kolokolnikov
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On the applications of Extremal Graph Theory to Coding Theory and Cryptography
<p>Explicit constructions in Extremal graph theory give appropriate lower bound for Turan type problems. In the case of prohibited cycles explicit constructions can be used in various problems of Information Security. We observe algebraic constructions of regular graphs of large girth and graphs with large cycle indicator and describe ...
Monika Polak
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On a valence problem in extremal graph theory
Vorliegende Arbeit bezieht sich auf nicht-orientierte, Schlingen und mehrfache Kanten nicht enhaltende Graphen. Bezeichne \(L\) einen solchen vom vollständigen \(p\)-Graphen \(K_p\) verschiedenen \(p\)-chromatischen Graphen, welcher eine Kante \(e\) so enthält, daß \(L-e\) ein \((p-1)\)-chromatischer Graph ist. Als Hauptergebnis der vorliegenden Arbeit
M Simonovits
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On tricyclic graphs with maximum atom–bond sum–connectivity index [PDF]
The sum-connectivity, Randić, and atom-bond connectivity indices have a prominent place among those topological indices that depend on the graph's vertex degrees.
Sadia Noureen +5 more
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