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Problems in extremal graph theory [PDF]
, 2010 We consider a variety of problems in extremal graph and set theory. The {\em chromatic number} of $G$, $\chi(G)$, is the smallest integer $k$ such that $G$ is $k$-colorable.
Lale Özkahya
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Two Extremal Problems in Graph Theory
The Electronic Journal of Combinatorics, 1994 We consider the following two problems. (1) Let $t$ and $n$ be positive integers with $n\geq t\geq 2$. Determine the maximum number of edges of a graph of order $n$ that contains neither $K_t$ nor $K_{t,t}$ as a subgraph. (2) Let $r$, $t$ and $n$ be positive integers with $n\geq rt$ and $t\geq 2$. Determine the maximum number of edges of a graph of
Richard A. Brualdi, Stephen Mellendorf
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On a valence problem in extremal graph theory
Discrete Mathematics, 1973 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
P. Erdös, Miklós Simonovits
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On a problem in extremal graph theory
Journal of Combinatorial Theory, Series B, 1977 From the authors introduction. Let \(G(n,m)\) denote a graph \((V,E)\) with \(n\) vertices and \(m\) edges and \(K_1\) a complete graph with \(i\) vertices. \textit{P.Turán} proved that every \(G(n,T(n,k))\) contains a \(K_k\), where \[ T(n,k) = \frac{k-2}{2(k-1)}(n^2-r^2)+\binom r2+1, \] \(r\equiv n(\mod k-1)\) and \(0\leq r\leq k-2\).
D.T Busolini, P. Erdös
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Some problems in extremal graph theory avoiding the use of the regularity lemma
, 2009 In this thesis we present two results in Extremal Graph Theory. The first result is a new proof of a conjecture of Bollobas on embedding trees of bounded degree. The second result is a new proof of the Posa conjecture.Let G=(W,E) be a graph on n vertices having minimum degree at least n/2 + c log(n), where c is a constant.
Ian Levitt
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EXTREMAL PROBLEMS IN GRAPH THEORY: A COMBINATORIAL OPTIMIZATION PERSPECTIVE
Advances and Applications in Discrete MathematicsThe extremal theory of graphs considers the study of how large or small a graph invariant may be, according to certain constraints. The field crosses the overlying with combinatorial optimization, in which optimal configurations are studied under discrete conditions.
R. Thangathamizh +2 more
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Some Problems in Algebraic and Extremal Graph Theory.
, 1995 Edward Dobson, Edward Dobson
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Extremal Problems in Discrete Geometry and Spectral Graph Theory
, 2019 Igor Balla
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A note on the Ramsey numbers for theta graphs versus the wheel of order 5
AKCE International Journal of Graphs and Combinatorics, 2018 The study of exact values and bounds on the Ramsey numbers of graphs forms an important family of problems in the extremal graph theory. For a set of graphs S and a graph F , the Ramsey number R (S , F) is the smallest positive integer r such that for ...
Mohammed M.M. Jaradat +3 more
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Hypergraphs with infinitely many extremal constructions
Discrete Analysis, 2023 Hypergraphs with infinitely many extremal constructions, Discrete Analysis 2023:18, 34 pp. A fundamental result in extremal graph theory, Turán's theorem, states that the maximal number of edges of a graph with $n$ vertices that does not contain a ...
Jianfeng Hou +4 more
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