Search results for "property."

showing 10 items of 926 documents

Two-Variable First-Order Logic with Equivalence Closure

2012

We consider the satisfiability and finite satisfiability problems for extensions of the two-variable fragment of first-order logic in which an equivalence closure operator can be applied to a fixed number of binary predicates. We show that the satisfiability problem for two-variable, first-order logic with equivalence closure applied to two binary predicates is in 2-NExpTime, and we obtain a matching lower bound by showing that the satisfiability problem for two-variable first-order logic in the presence of two equivalence relations is 2-NExpTime-hard. The logics in question lack the finite model property; however, we show that the same complexity bounds hold for the corresponding finite sa…

Discrete mathematicsGeneral Computer ScienceLogical equivalenceFinite model propertyGeneral MathematicsDescriptive complexity theorySatisfiabilityDecidabilityFirst-order logicCombinatoricsTheoryofComputation_MATHEMATICALLOGICANDFORMALLANGUAGESComputer Science::Logic in Computer ScienceMaximum satisfiability problemClosure operatorEquivalence relationBoolean satisfiability problemMathematics2012 27th Annual IEEE Symposium on Logic in Computer Science
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A comparison of compatible, finite, and inductive graph properties

1993

Abstract In the theory of hyperedge-replacement grammars and languages, one encounters three types of graph properties that play an important role in proving decidability and structural results. The three types are called compatible, finite, and inductive graph properties. All three of them cover graph properties that are well-behaved with respect to certain operations on hypergraphs. In this paper, we show that the three notions are essentially equivalent. Consequently, three lines of investigation in the theory of hyperedge replacement - so far separated - merge into one.

Discrete mathematicsGeneral Computer ScienceVoltage graphDirected graphDecidabilityTheoretical Computer ScienceCombinatoricsVertex-transitive graphRule-based machine translationClique-widthGraph propertyNull graphMathematicsComputer Science(all)Theoretical Computer Science
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Fixed point results for F-contractive mappings of Hardy-Rogers-type

2014

Recently, Wardowski introduced a new concept of contraction and proved a fixed point theorem which generalizes Banach contraction principle. Following this direction of research, in this paper, we will present some fixed point results of Hardy-Rogers-type for self-mappings on complete metric spaces or complete ordered metric spaces. Moreover, an example is given to illustrate the usability of the obtained results.

Discrete mathematicsGeneral MathematicsInjective metric spaceMetric spaces ordered metric spaces fixed points F-contractions of Hardy-Rogers-typeFixed-point theoremFixed pointFixed-point propertyConvex metric spaceUniform continuitySettore MAT/05 - Analisi MatematicaFréchet spaceContraction mappingMathematicsFilomat
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Further generalization of fixed point theorems in Menger PM-spaces

2015

In this work, we establish some fixed point theorems by revisiting the notion of ψ-contractive mapping in Menger PM-spaces. One of our results (namely, Theorem 2.3) may be viewed as a possible answer to the problem of existence of a fixed point for generalized type contractive mappings in M-complete Menger PM-spaces under arbitrary t-norm. Some examples are furnished to demonstrate the validity of the obtained results.

Discrete mathematicsGeneralizationApplied MathematicsFixed-point theoremType (model theory)Fixed pointMenger PM-spaceFixed-point propertyMenger's theoremfixed pointψ-contractive mappingDifferential geometrySettore MAT/05 - Analisi MatematicaGeometry and TopologyCoincidence pointMathematicsFixed Point Theory and Applications
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Fixed point and homotopy results for mixed multi-valued mappings in 0-complete partial metric spaces*

2015

We give sufficient conditions for the existence of common fixed points for a pair of mixed multi-valued mappings in the setting of 0-complete partial metric spaces. An example is given to demonstrate the usefulness of our results over the existing results in metric spaces. Finally, we prove a homotopy theorem via fixed point results.

Discrete mathematicsHomotopy categoryPartial metric spacefixed pointsApplied MathematicsInjective metric spacepartial metric spaceslcsh:QA299.6-433multi-valued mappingslcsh:AnalysisFixed pointFixed-point propertyIntrinsic metricConvex metric spacen-connectedMetric spaceSettore MAT/05 - Analisi Matematicamulti-valued mappingMetric (mathematics)AnalysisMathematics
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Fixed point theory in partial metric spaces via φ-fixed point’s concept in metric spaces

2014

Abstract Let X be a non-empty set. We say that an element x ∈ X is a φ-fixed point of T, where φ : X → [ 0 , ∞ ) and T : X → X , if x is a fixed point of T and φ ( x ) = 0 . In this paper, we establish some existence results of φ-fixed points for various classes of operators in the case, where X is endowed with a metric d. The obtained results are used to deduce some fixed point theorems in the case where X is endowed with a partial metric p. MSC:54H25, 47H10.

Discrete mathematicsInjective metric spaceApplied Mathematicsmetric spacepartial metric spaceFixed-point theoremFixed pointFixed-point propertyIntrinsic metricConvex metric spaceIsolated pointMetric spacefixed pointSettore MAT/05 - Analisi MatematicaDiscrete Mathematics and Combinatorics$\varphi$-fixed pointAnalysisMathematicsJournal of Inequalities and Applications
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A Suzuki type fixed point theorem for a generalized multivalued mapping on partial Hausdorff metric spaces

2013

Abstract In this paper, we obtain a Suzuki type fixed point theorem for a generalized multivalued mapping on a partial Hausdorff metric space. As a consequence of the presented results, we discuss the existence and uniqueness of the bounded solution of a functional equation arising in dynamic programming.

Discrete mathematicsInjective metric spacepartial metric spaceFixed-point theoremFixed-point propertyCommon fixed pointSchauder fixed point theoremHausdorff distanceSettore MAT/05 - Analisi Matematicamulti-valued mappingContraction mappingGeometry and TopologyBrouwer fixed-point theoremKakutani fixed-point theoremMathematicsTopology and its Applications
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Polynomial growth and identities of superalgebras and star-algebras

2009

Abstract We study associative algebras with 1 endowed with an automorphism or antiautomorphism φ of order 2, i.e., superalgebras and algebras with involution. For any fixed k ≥ 1 , we construct associative φ -algebras whose φ -codimension sequence is given asymptotically by a polynomial of degree k whose leading coefficient is the largest or smallest possible.

Discrete mathematicsInvolution (mathematics)Settore MAT/02 - AlgebraPure mathematicsAlgebra and Number TheoryCodimensionAutomorphismAssociative property\varphi$-identity $T^\varphi$-ideal $\varphi$-codimensions growthMathematicsJournal of Pure and Applied Algebra
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Unified Metrical Common Fixed Point Theorems in 2-Metric Spaces via an Implicit Relation

2013

We prove some common fixed point theorems for two pairs of weakly compatible mappings in 2-metric spaces via an implicit relation. As an application to our main result, we derive Bryant's type generalized fixed point theorem for four finite families of self-mappings which can be utilized to derive common fixed point theorems involving any finite number of mappings. Our results improve and extend a host of previously known results. Moreover, we study the existence of solutions of a nonlinear integral equation.

Discrete mathematicsLeast fixed point2-metric space common property (E.A) common limit range property weakly compatible mappings implicit relations fixed point.Metric spaceSchauder fixed point theoremArticle SubjectSettore MAT/05 - Analisi MatematicaFixed-point theoremType (model theory)Fixed-point propertyCoincidence pointFinite setMathematicsJournal of Operators
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A fixed point theorem inG-metric spaces viaα-series

2014

In the context of G -metric spaces we prove a common fixed point theorem for a sequence of self mappings using a new concept of α-series. Keywords: α-series, common fixed point, G -metric space Quaestiones Mathematicae 37(2014), 429-434

Discrete mathematicsLeast fixed pointMetric spaceMathematics (miscellaneous)Fréchet spaceFixed-point theoremFixed-point propertyBrouwer fixed-point theoremKakutani fixed-point theoremCoincidence pointMathematicsQuaestiones Mathematicae
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