Search results for "Number"

showing 10 items of 3939 documents

Thin bases of order h

2003

Abstract A subset A⊆ N 0 is called a basis of order h if every positive integer can be represented as a sum of h members of A . Thin bases of order h will be constructed in this paper, for each h ⩾2, where the value of lim sup A(n)/ n h is smaller than that of thin bases known so far. In the most important case h =2 it is shown that for the considered class of bases (which generalizes an ansatz of Stohr) the result is best possible up to an e >0.

Discrete mathematicsCombinatoricsClass (set theory)Algebra and Number TheoryIntegerOrder (group theory)Value (computer science)Basis (universal algebra)MathematicsAnsatzJournal of Number Theory
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Mixed intersections of non quasi-analytic classes

2008

Given two semi-regular matrices M and M' and two open subsets O and O' [resp. two compact subsets K and K'] of Rr and Rs respectively, we introduce the spaces E(M×M')(O × O') and D(M×M')(O × O') [resp. D(M×M')(K × K')]. In this paper we study their locally convex properties and the structure of their elements. This leads in [10] to tensor product representations of these spaces and to some kernel theorems.

Discrete mathematicsCombinatoricsComputational MathematicsAlgebra and Number TheoryTensor productKernel (set theory)Applied MathematicsStructure (category theory)Regular polygonGeometry and TopologyAnalysisMathematicsRevista de la Real Academia de Ciencias Exactas, Fisicas y Naturales. Serie A. Matematicas
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Über die Schnittzahlen mehrfach balancierter blockpläne

1991

Abstract For a finite incidence structure D with a set X of blocks let [ X ] be the number of points common with all blocks contained in X . We define the functions M(t)(B1,…; B1)=ΣB [B1, B]…[B1,B], and, for every partition ϖ = ϖ1,…,ϖ1) of t, the function Mϖ(B1,…,B1) = Σ Πm [Bi | i ϵ Rm], sum over all decompositions {l, …, t} = R1, ⊃ … ⊃ Rl, |Rm| = ϖm. We show: If D is t-fold balanced, then M(t) = Σϖ cϖMϖ, where the, coefficients cϖ are linear combinations of the parameters b1,…,bt, the constant numbers of blocks through any l,…, t distinct points. Conversely, if the rank of the b × b-matrix ([B, B∗])B,B∗ is equal to the number ν of points and M(t) is a rational linear combination of the fu…

Discrete mathematicsCombinatoricsComputational Theory and MathematicsIncidence structureDiscrete Mathematics and CombinatoricsPartition (number theory)Linear combinationTheoretical Computer ScienceBlock designMathematicsJournal of Combinatorial Theory, Series A
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Kolmogorov numberings and minimal identification

1997

Abstract Identification of programs for computable functions from their graphs by algorithmic devices is a well studied problem in learning theory. Freivalds and Chen consider identification of ‘minimal’ and ‘nearly minimal’ programs for functions from their graphs. To address certain problems in minimal identification for Godel numberings, Freivalds later considered minimal identification in Kolmogorov numberings. Kolmogorov numberings are in some sense optimal numberings and have some nice properties. We prove certain separation results for minimal identification in every Kolmogorov numbering. In addition we also compare minimal identification in Godel numberings versus minimal identifica…

Discrete mathematicsCombinatoricsIdentification (information)Computable functionGeneral Computer ScienceNumberingComputer Science(all)Theoretical Computer ScienceMathematicsTheoretical Computer Science
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On lazy representations and Sturmian graphs

2011

In this paper we establish a strong relationship between the set of lazy representations and the set of paths in a Sturmian graph associated with a real number α. We prove that for any non-negative integer i the unique path weighted i in the Sturmian graph associated with α represents the lazy representation of i in the Ostrowski numeration system associated with α. Moreover, we provide several properties of the representations of the natural integers in this numeration system.

Discrete mathematicsCombinatoricsOstrowski numerationIntegernumeration systems Sturmian graphs continued fractionsSettore INF/01 - InformaticaGraphMathematicsReal number
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Subvarieties of the Varieties Generated by the SuperalgebraM1, 1(E) orM2(𝒦)

2003

Abstract Let 𝒦 be a field of characteristic zero, and let us consider the matrix algebra M 2(𝒦) endowed with the ℤ2-grading (𝒦e 11 ⊕ 𝒦e 22) ⊕ (𝒦e 12 ⊕ 𝒦e 21). We define two superalgebras, ℛ p and 𝒮 q , where p and q are positive integers. We show that if 𝒰 is a proper subvariety of the variety generated by the superalgebra M 2(𝒦), then the even-proper part of the T 2-ideal of graded polynomial identities of 𝒰 asymptotically coincides with the even-proper part of the graded polynomial identities of the variety generated by the superalgebra ℛ p  ⊕ 𝒮 q . This description also affords an even-asymptotic desc…

Discrete mathematicsCombinatoricsPolynomialAlgebra and Number TheorySubvarietyMatrix algebraZero (complex analysis)Field (mathematics)Variety (universal algebra)SuperalgebraMathematicsCommunications in Algebra
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Graphes connexes représentation des entiers et équirépartition

1983

Abstract Let q be an integer ≥2 and Ω a suitable subset of {0,…,q − 1}2; C (q; Ω) denotes the set of natural integers, the pairs of successive q-adic digits of which are in Ω. If P is an irrational polynomial, the sequence (P(n): n ∈ C (q; Ω)) is uniformly distributed modulo one.

Discrete mathematicsCombinatoricsPolynomialSequenceAlgebra and Number TheoryIntegerModuloMathematics::Number TheoryMathematicsJournal of Number Theory
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On the Distribution ofB3-Sequences

1996

Abstract An infinite set of natural numbers is called aB3-sequence if all sumsa1+a2+a3withaj∈Aanda1⩽a2⩽a3are distinct. LetA(n) be the number of positive elements ⩽ninA. P. Erdos conjectures that everyB3-sequenceAsatisfies lim infn→∞ A(n) n−1/3=0. In this paper we prove that no sequence satisfyingA(n)∼αn1/3can be aB3-sequence. We also give other necessary conditions for aB3-sequence.

Discrete mathematicsCombinatoricsSequenceInfinite setAlgebra and Number TheoryDistribution (number theory)Natural numberMathematicsJournal of Number Theory
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Codimension growth of two-dimensional non-associative algebras

2007

Let F be a field of characteristic zero and let A be a two-dimensional non-associative algebra over F. We prove that the sequence c n (A), n =1,2,..., of codimensions of A is either bounded by n + 1 or grows exponentially as 2 n . We also construct a family of two-dimensional algebras indexed by rational numbers with distinct T-ideals of polynomial identities and whose codimension sequence is n + 1, n > 2.

Discrete mathematicsCombinatoricsSequencePolynomialRational numberApplied MathematicsGeneral MathematicsBounded functionZero (complex analysis)Field (mathematics)CodimensionIdeal (ring theory)MathematicsProceedings of the American Mathematical Society
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On the family ofr-regular graphs with Grundy numberr+1

2014

Abstract The Grundy number of a graph G , denoted by Γ ( G ) , is the largest k such that there exists a partition of V ( G ) , into k independent sets V 1 , … , V k and every vertex of V i is adjacent to at least one vertex in V j , for every j i . The objects which are studied in this article are families of r -regular graphs such that Γ ( G ) = r + 1 . Using the notion of independent module, a characterization of this family is given for r = 3 . Moreover, we determine classes of graphs in this family, in particular, the class of r -regular graphs without induced C 4 , for r ≤ 4 . Furthermore, our propositions imply results on the partial Grundy number.

Discrete mathematicsCombinatoricsVertex (graph theory)Grundy numberDiscrete Mathematics and CombinatoricsPartition (number theory)Regular graphGraphTheoretical Computer ScienceMathematicsDiscrete Mathematics
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