Results 21 to 30 of about 934 (196)
Problems in Extremal and Probabilistic Combinatorics. [PDF]
, 2012 Extremal combinatorics can be described as a subfield of combinatorics that studies the maximum or minimum size of discrete structures (such as graphs, set systems, or convex bodies) with certain properties. For example, a classical question of this kind is, ``what is the maximum number of edges that a triangle-free graph can have?''.
Lee, Choongbum
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Probabilistic models for the analysis of inverse extremal problems in combinatorics [PDF]
Vestnik Samarskogo Gosudarstvennogo Tehničeskogo Universiteta. Seriâ: Fiziko-Matematičeskie Nauki, 2022 In an inverse extremal problem for a combinatorial scheme with a given value of the objective function of the form of a certain extreme value of its characteristic, a probabilistic model is developed that ensures that this value is obtained in its ...
Nataliya Yu. Enatskaya
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Exponential multivalued forbidden configurations [PDF]
Discrete Mathematics & Theoretical Computer Science, 2021 The forbidden number $\mathrm{forb}(m,F)$, which denotes the maximum number of unique columns in an $m$-rowed $(0,1)$-matrix with no submatrix that is a row and column permutation of $F$, has been widely studied in extremal set theory.
Travis Dillon, Attila Sali
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Ramsey numbers of cycles versus general graphs
Forum of Mathematics, Sigma, 2023 The Ramsey number $R(F,H)$ is the minimum number N such that any N-vertex graph either contains a copy of F or its complement contains H. Burr in 1981 proved a pleasingly general result that, for any graph H, provided n is sufficiently large, a ...
John Haslegrave +3 more
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Treewidth computation and extremal combinatorics [PDF]
Combinatorica, 2008 For a given graph G and integers b,f >= 0, let S be a subset of vertices of G of size b+1 such that the subgraph of G induced by S is connected and S can be separated from other vertices of G by removing f vertices. We prove that every graph on n vertices contains at most n\binom{b+f}{b} such vertex subsets.
Fedor V. Fomin, Yngve Villanger
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Extremal combinatorics in generalized Kneser graphs [PDF]
, 2009 This thesis focuses on the interplay of extremal combinatorics and finite geometry. Combinatorics is concerned with discrete (and usually finite) objects. Extremal combinatorics studies how large or how small a collection of finite objects can be under certain restrictions. Those objects can be sets, graphs, vectors, etc.
Mussche, T.J.J.
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Chromatic Turán problems and a new upper bound for the Turán density of $\mathcal{K}_4^-$ [PDF]
Discrete Mathematics & Theoretical Computer Science, 2005 We consider a new type of extremal hypergraph problem: given an $r$-graph $\mathcal{F}$ and an integer $k≥2$ determine the maximum number of edges in an $\mathcal{F}$-free, $k$-colourable $r$-graph on $n$ vertices.
John Talbot
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On the conjunctive capacity of graphs [PDF]
, 2013 The investigation of the asymptotic behaviour of various graph parameters in powers of a fixed graph G=(V,E) is motivated by problems in information theory and extremal ...
Chlebikova, Janka +5 more
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On the quaternion projective space
Journal of Taibah University for Science, 2020 Apart from being a vital and exciting field in mathematics with interesting results, projective spaces have various applications in design theory, coding theory, physics, combinatorics, number theory and extremal combinatorial problems. In this paper, we
Y. Omar +4 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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