Results 31 to 40 of about 934 (196)
An Extremal Problem for Finite Lattices
Theory and Applications of Graphs, 2016 For a fixed M x N integer lattice L(M,N), we consider the maximum size of a subset A of L(M,N) which contains no squares of prescribed side lengths k(1),...,k(t).
John Goldwasser +2 more
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Theory of combinatorial limits and extremal combinatorics [PDF]
In the past years, techniques from different areas of mathematics have been successfully applied in extremal combinatorics problems. Examples include applications of number theory, geometry and group theory in Ramsey theory and analytical methods to different problems in extremal combinatorics.\ud By providing an analytic point of view of many discrete
Lopes Martins, Taísa
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The topological symmetric orbifold
Journal of High Energy Physics, 2020 We analyze topological orbifold conformal field theories on the symmetric product of a complex surface M. By exploiting the mathematics literature we show that a canonical quotient of the operator ring has structure constants given by Hurwitz numbers ...
Songyuan Li, Jan Troost
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A question of Bukh on sums of dilates
Discrete Analysis, 2021 A question of Bukh on sums of dilates, Discrete Analysis 2021:13, 21 pp. Let $A$ and $B$ be subsets of an Abelian group. Their sumset $A+B$ is defined to be the set of all $a+b$ such that $a\in A$ and $b\in B$.
Brandon Hanson, Giorgis Petridis
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List graphs and distance-consistent node labelings
Electronic Journal of Graph Theory and Applications, 2018 In this paper we consider node labelings c of an undirected connected graph G = (V, E) with labels {1, 2, ..., ∣V∣}, which induce a list distance c(u, v) = ∣c(v) − c(u)∣ besides the usual graph distance d(u, v).
Håkan Lennerstad, Mattias Eriksson
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Excluded subposets in the Boolean lattice [PDF]
Discrete Mathematics & Theoretical Computer Science, 2005 We are looking for the maximum number of subsets of an n-element set not containing 4 distinct subsets satisfying $A ⊂B, C ⊂B, C ⊂D$. It is proved that this number is at least the number of the $\lfloor \frac{n }{ 2}\rfloor$ -element sets times $1+\frac ...
Gyula O.H. Katona
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Extremal trees with fixed degree sequence
, 2021 The greedy tree G(D) and the M-tree M(D) are known to be extremal among trees with degree sequence D with respect to various graph invariants. This paper provides a general theorem that covers a large family of invariants for which G(D) or M(D) is ...
Andriantiana, Eric O. D., +5 more
core +1 more source
A characterization of extremal graphs with no matching-cut [PDF]
Discrete Mathematics & Theoretical Computer Science, 2005 A graph is called (matching-)immune if it has no edge cut that is also a matching. Farley and Proskurowski proved that for all immune graphs $G=(V,E)$, $|E|≥\lceil 3(|V|-1)/2\rceil$ , and constructed a large class of immune graphs that attain this lower ...
Paul Bonsma
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Random multilinear maps and the Erdős box problem
Discrete Analysis, 2021 Random multilinear maps and the Erdős box problem, Discrete Analysis 2021:17, 8 pp. A major theme in extremal combinatorics is determining the maximum number of edges that a graph or hypergraph can have if it does not contain a certain fixed graph or ...
David Conlon +2 more
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An extremal problem on trees and database theory [PDF]
Discrete Mathematics & Theoretical Computer Science, 2005 We consider an extremal problem on labelled directed trees and applications to database theory. Among others, we will show explicit keysystems on an underlying set of size $n$, that cannot be represented by a database of less than $2^{n(1-c\cdot \log ...
Gyula O.H. Katona, Krisztián Tichler
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