transitive. A partially ordered set (poset for short) is an ordered pair P = ( X , ≤ ) {\displaystyle P=(X,\leq )} consisting of a set X {\displaystyle...
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Total order (redirect from Total ordered set)
the partially ordered set is a set of subsets of a given set that is ordered by inclusion, and the term is used for stating properties of the set of the...
22 KB (3,150 words) - 14:08, 21 April 2025
In abstract algebra, a partially ordered group is a group (G, +) equipped with a partial order "≤" that is translation-invariant; in other words, "≤"...
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and combinatorics, Dilworth's theorem states that, in any finite partially ordered set, the maximum size of an antichain of incomparable elements equals...
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Complete partial order (redirect from Directed-complete partially ordered set)
used to refer to at least three similar, but distinct, classes of partially ordered sets, characterized by particular completeness properties. Complete partial...
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mathematical symbols Order theory Partially ordered set Directional symbols Polynomial-time reduction Cooley, Brandon. "Ordered Sets" (PDF) (Lecture note for:...
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In set theory, a tree is a partially ordered set ( T , < ) {\displaystyle (T,<)} such that for each t ∈ T {\displaystyle t\in T} , the set { s ∈ T : s...
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Maximal and minimal elements (section Directed sets)
{\displaystyle S} is again defined dually. In the particular case of a partially ordered set, while there can be at most one maximum and at most one minimum...
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is a fundamental property of the real numbers. More generally, a partially ordered set X has the least-upper-bound property if every non-empty subset of...
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Zorn's lemma (category Lemmas in set theory)
proposition of set theory. It states that a partially ordered set containing upper bounds for every chain (that is, every totally ordered subset) necessarily...
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Atom (order theory) (redirect from Atomic set)
In the mathematical field of order theory, an element a of a partially ordered set with least element 0 is an atom if 0 < a and there is no x such that...
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a partially ordered set such that any two distinct elements in the subset are incomparable. The size of the largest antichain in a partially ordered set...
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In mathematics, an upper set (also called an upward closed set, an upset, or an isotone set in X) of a partially ordered set ( X , ≤ ) {\displaystyle...
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Order theory (section Partially ordered sets)
then a ≤ c (transitivity). A set with a partial order on it is called a partially ordered set, poset, or just ordered set if the intended meaning is clear...
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Lattice (order) (section As partially ordered set)
subdisciplines of order theory and abstract algebra. It consists of a partially ordered set in which every pair of elements has a unique supremum (also called...
41 KB (5,834 words) - 13:33, 28 April 2025
Hasse diagram (category Graphical concepts in set theory)
represent a finite partially ordered set, in the form of a drawing of its transitive reduction. Concretely, for a partially ordered set ( S , ≤ ) {\displaystyle...
11 KB (1,342 words) - 10:38, 16 December 2024
Cofinality (category Set theory)
mathematics, especially in order theory, the cofinality cf(A) of a partially ordered set A is the least of the cardinalities of the cofinal subsets of A...
8 KB (1,345 words) - 05:54, 25 February 2025
specifically order theory, the join of a subset S {\displaystyle S} of a partially ordered set P {\displaystyle P} is the supremum (least upper bound) of S , {\displaystyle...
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(abbreviated inf; pl.: infima) of a subset S {\displaystyle S} of a partially ordered set P {\displaystyle P} is the greatest element in P {\displaystyle...
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Closure operator (redirect from Closure operator on a set)
(Y):Y\subseteq X{\text{ and }}Y{\text{ finite}}\right\}.} In the theory of partially ordered sets, which are important in theoretical computer science, closure operators...
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any partially ordered set, every totally ordered subset is contained in a maximal totally ordered subset, where "maximal" is with respect to set inclusion...
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set of real numbers is bounded if and only if it has an upper and lower bound. This definition is extendable to subsets of any partially ordered set....
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Dedekind cut (section Partially ordered sets)
mathematician Norberto Cuesta Dutari [es]. More generally, if S is a partially ordered set, a completion of S means a complete lattice L with an order-embedding...
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theory, the greatest element of a subset S {\displaystyle S} of a partially ordered set (poset) is an element of S {\displaystyle S} that is greater than...
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Weak ordering (redirect from Ordered partition of a set)
(rankings without ties) and are in turn generalized by (strictly) partially ordered sets and preorders. There are several common ways of formalizing weak...
30 KB (4,360 words) - 12:57, 6 October 2024
chain is a totally ordered set or a totally ordered subset of a poset. See also total order. Chain complete. A partially ordered set in which every chain...
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s(I)} be the set of non-empty finite totally ordered subsets, which itself is partially ordered by inclusion. Every partially ordered set can be considered...
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specifically order theory, the Dedekind–MacNeille completion of a partially ordered set is the smallest complete lattice that contains it. It is named after...
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Directed sets are a generalization of nonempty totally ordered sets. That is, all totally ordered sets are directed sets (contrast partially ordered sets, which...
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In order-theoretic mathematics, a graded partially ordered set is said to have the Sperner property (and hence is called a Sperner poset), if no antichain...
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