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Information Inequalities via Submodularity and a Problem in Extremal Graph Theory. [PDF]
Entropy (Basel), 2022 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. It applies this approach for the derivation of information inequalities with Shannon information measures.
Sason I.
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On some interconnections between combinatorial optimization and extremal graph theory [PDF]
Yugoslav Journal of Operations Research, 2004 The uniting feature of combinatorial optimization and extremal graph theory is that in both areas one should find extrema of a function defined in most cases on a finite set.
Cvetković Dragoš M. +2 more
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On an extremal problem in graph theory [PDF]
Colloquium Mathematicum, 1964 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
Péter L. Erdős
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An extremal problem in graph theory II [PDF]
Journal of the Australian Mathematical Society, 1980 AbstractWe contine our study of the following combinatorial problem: What is the largest integer N = N (t, m, p) for which there exists a set of N people satisfying the following conditions: (a) each person speaks t languages, (b) among any m people there are two who speak a common language and (c) at most p speak a common language.
H. L. Abbott, Meir Katchalski, A. C. Liu
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An extremal problem in graph theory [PDF]
Journal of the Australian Mathematical Society, 1970 G(n;l) will denote a graph of n vertices and l edges. Let f0(n, k) be the smallest integer such that there is a G (n;f0(n, k)) in which for every set of k vertices there is a vertex joined to each of these. Thus for example fo = 3 since in a triangle each pair of vertices is joined to a third.
P. Erdös, Leo Moser
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On some extremal problems in graph theory [PDF]
, 1999 In this paper we are concerned with various graph invariants (girth, diameter, expansion constants, eigenvalues of the Laplacian, tree number) and their analogs for weighted graphs -- weighing the graph changes a combinatorial problem to one in analysis. We study both weighted and unweighted graphs which are extremal for these invariants.
Dmitry Jakobson, Igor Rivin
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Turan problems in extremal graph theory and flexibility
, 2021 In this work we will study two distinct areas of graph theory: generalized Turan problems and graph flexibility. In the first chapter, we will provide some basic definitions and motivation. Chapters 2 and 3 contain two submitted papers showing that two graphs, the cycle on five vertices and the path on four vertices, are maximized by the Turan graph ...
Kyle Murphy
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Problems in extremal graphs and poset theory
, 2018 In this dissertation, we present three different research topics and results regarding such topics. We introduce partially ordered sets (posets) and study two types of problems concerning them-- forbidden subposet problems and induced-poset-saturation problems. We conclude by presenting results obtained from studying vertex-identifying codes in graphs.
Shanise Walker
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Problems in extremal graph theory and Euclidean Ramsey theory
, 2019 This thesis addresses problems of three types. The first type is finding extremal numbers for unions of graphs, each with a colour-critical edge (joint work with V. Nikiforov). In 1968, Simonovits found extremal numbers $ex(n,H)$ for graphs with a colour-critical edge for large $n$ (without specifying how large).
Sergei Tsaturian
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Problems in Ramsey theory, probabilistic combinatorics and extremal graph theory
, 2015 In this dissertation, we treat several problems in Ramsey theory, probabilistic combinatorics and extremal graph theory.
Bhargav Narayanan
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