Results 31 to 40 of about 13,803 (191)
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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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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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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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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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
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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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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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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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Pairwise Intersections and Forbidden Configurations [PDF]
Discrete Mathematics & Theoretical Computer Science, 2005 Let $f_m(a,b,c,d)$ denote the maximum size of a family $\mathcal{F}$ of subsets of an $m$-element set for which there is no pair of subsets $A,B \in \mathcal{F}$ with $|A \cap B| \geq a$, $|\bar{A} \cap B| \geq b$, $|A \cap \bar{B}| \geq c$, and $|\bar{A}
Richard P. Anstee, Peter Keevash
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Extremal words in morphic subshifts [PDF]
, 2013 Given an infinite word X over an alphabet A a letter b occurring in X, and a total order \sigma on A, we call the smallest word with respect to \sigma starting with b in the shift orbit closure of X an extremal word of X.
Currie, James D. +3 more
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