Results 31 to 40 of about 887,124 (211)
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
doaj +1 more source
, 2014 Positional games are a branch of combinatorics, researching a variety of two-player games, ranging from popular recreational games such as Tic-Tac-Toe and Hex, to purely abstract games played on graphs and hypergraphs.
Krivelevich, Michael
core +1 more source
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
doaj +1 more source
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
doaj +1 more source
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
doaj +1 more source
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
doaj +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
doaj +1 more source
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
doaj +1 more source
Supersaturation and stability for forbidden subposet problems [PDF]
, 2015 We address a supersaturation problem in the context of forbidden subposets. A family $\mathcal{F}$ of sets is said to contain the poset $P$ if there is an injection $i:P \rightarrow \mathcal{F}$ such that $p \le_P q$ implies $i(p) \subset i (q)$.
Patkos, Balazs
core +5 more sources
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
doaj +1 more source