Results 31 to 40 of about 8,142 (223)
Diagonal Forms, Linear Algebraic Methods and Ramsey-Type Problems [PDF]
This thesis focuses mainly on linear algebraic aspects of combinatorics. Let N_t(H) be an incidence matrix with edges versus all subhypergraphs of a complete hypergraph that are isomorphic to H. Richard M.
Wong, Wing Hong Tony
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The goal of this paper is to give a new, abstract approach to cover-decomposition and polychromatic colorings using hypergraphs on ordered vertex sets.
Balázs Keszegh, Dömötör Pálvölgyi
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Let $\text{Tr}(n,m,k)$ denote the largest number of distinct projections onto $k$ coordinates guaranteed in any family of $m$ binary vectors of length $n$. The classical Sauer-Perles-Shelah Lemma implies that $\text{Tr}(n, n^r, k) = 2^k$ for $k \le r$. While determining $\text{Tr}(n,n^r,k)$ precisely for general $k$ seems hopeless even for constant $r$,
Noga Alon, Guy Moshkovitz, Noam Solomon
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On partitioning of hypergraphs
The edge-isoperimetric problem on graphs (EIP), namely for a given integer \(m\) and graph \(G=(V,E)\) to find a subset \(A\) of the vertices of \(G\) of cardinality \(m\) so that the number of edges of \(G\) connecting vertices in \(A\) to vertices in \(V\setminus A\), is minimized (version 1), or such that the number of edges of \(G\) induced by \(A\)
S. Bezrukov, Battiti, Roberto
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On Matchings in Hypergraphs [PDF]
We show that if the largest matching in a $k$-uniform hypergraph $G$ on $n$ vertices has precisely $s$ edges, and $n>2k^2s/\log k$, then $H$ has at most $\binom n k - \binom {n-s} k $ edges and this upper bound is achieved only for hypergraphs in which the set of edges consists of all $k$-subsets which intersect a given set of $s$ vertices.
Peter Frankl +2 more
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07281 Open Problems – Structure Theory and FPT Algorithmcs for Graphs, Digraphs and Hypergraphs [PDF]
The following is a list of the problems presented on Monday, July 9, 2007 at the open-problem session of the Seminar on Structure Theory and FPT Algorithmics for Graphs, Digraphs and Hypergraphs, held at Schloss Dagstuhl in Wadern ...
Stege, Ulrike +3 more
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Maximizing Spectral Radii of Uniform Hypergraphs with Few Edges
In this paper we investigate the hypergraphs whose spectral radii attain the maximum among all uniform hypergraphs with given number of edges. In particular we characterize the hypergraph(s) with maximum spectral radius over all unicyclic hypergraphs ...
Fan Yi-Zheng +3 more
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Hypergraphs in m-Polar Fuzzy Environment
Fuzzy graph theory is a conceptual framework to study and analyze the units that are intensely or frequently connected in a network. It is used to study the mathematical structures of pairwise relations among objects. An m-polar fuzzy (mF, for short) set
Muhammad Akram, Gulfam Shahzadi
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Cartesian product of hypergraphs: properties and algorithms [PDF]
Cartesian products of graphs have been studied extensively since the 1960s. They make it possible to decrease the algorithmic complexity of problems by using the factorization of the product.
Alain Bretto +2 more
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Elementary definability of the class of universal hypergraphic automata in the class of semigroups [PDF]
Hypergraphic automata are automata, state sets and output symbol sets of which are hypergraphs, being invariant under actions of transition and output functions. Universally attracting objects in the category of hypergraphic automata are called universal
Molchanov, Vladimir Aleksandrovich +1 more
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