- family of sets with the finite intersection property
- Математика: центрированная система множеств
Универсальный англо-русский словарь. Академик.ру. 2011.
Универсальный англо-русский словарь. Академик.ру. 2011.
Finite intersection property — In general topology, the finite intersection property is a property of a collection of subsets of a set X . A collection has this property if the intersection over any finite subcollection of the collection is nonempty.DefinitionLet X be a set… … Wikipedia
Intersection number (graph theory) — In the mathematical field of graph theory, the intersection number of a graph is the smallest number of elements in a representation of G as an intersection graph of finite sets. Equivalently, it is the smallest number of cliques needed to cover… … Wikipedia
De Bruijn–Erdős theorem (graph theory) — This article is about coloring infinite graphs. For the number of lines determined by a finite set of points, see De Bruijn–Erdős theorem (incidence geometry). In graph theory, the De Bruijn–Erdős theorem, proved by Nicolaas Govert de Bruijn and… … Wikipedia
Compact space — Compactness redirects here. For the concept in first order logic, see compactness theorem. In mathematics, specifically general topology and metric topology, a compact space is an abstract mathematical space whose topology has the compactness… … Wikipedia
Union-closed sets conjecture — In combinatorial mathematics, the union closed sets conjecture is an elementary problem, posed by Péter Frankl in 1979 and still open as of 2008. A family of sets is said to be union closed if the union of any two sets from the family remains in… … Wikipedia
Locally finite collection — In the mathematical field of topology, local finiteness is a property of collections of subsets of a topological space. It is fundamental in the study of paracompactness and topological dimension. A collection of subsets of a topological space X… … Wikipedia
Compactness theorem — In mathematical logic, the compactness theorem states that a set of first order sentences has a model if and only if every finite subset of it has a model. This theorem is an important tool in model theory, as it provides a useful method for… … Wikipedia
Helly's theorem — In geometry, Helly s theorem is a basic combinatorial result on convex sets. It was proved by Eduard Helly in 1923, and gave rise to the notion of Helly family.tatement of Helly s theorem:Suppose that::X 1,X 2,dots,X n :is a finite collection of… … Wikipedia
Median graph — The median of three vertices in a median graph In mathematics, and more specifically graph theory, a median graph is an undirected graph in which any three vertices a, b, and c have a unique median: a vertex m(a,b,c) that belongs to shortest… … Wikipedia
Boolean algebras canonically defined — Boolean algebras have been formally defined variously as a kind of lattice and as a kind of ring. This article presents them more neutrally but equally formally as simply the models of the equational theory of two values, and observes the… … Wikipedia
mathematics — /math euh mat iks/, n. 1. (used with a sing. v.) the systematic treatment of magnitude, relationships between figures and forms, and relations between quantities expressed symbolically. 2. (used with a sing. or pl. v.) mathematical procedures,… … Universalium