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1.
In this paper, we study the notions related to tree property 1 (=TP1), or, equivalently, SOP2. Among others, we supply a type-counting criterion for TP1 and show the equivalence of TP1 and k- TP1. Then we introduce the notions of weak k- TP1 for k≥2, and also supply type-counting criteria for those. We do not know whether weak k- TP1 implies TP1, but at least we prove that each weak k- TP1 implies SOP1. Our generalization of the tree-indiscernibility results in D?amonja and Shelah (2004)[5] is crucially used throughout the paper.  相似文献   

2.
It is proved that for any algebraic polynomial P of degree at most n we have for 1 p ≤ + t8, x ≥ 1 the inequality For p ≥1 and x ≥ 1 we construct a polynomial P* of degree n for which   相似文献   

3.
For any integer n ≥ 2, let P(n) be the largest prime factor of n. In this paper, we prove that the number of primes p ≤ x with P(p-1) ≥ p~c is more than(1-c + o(1))π(x) for 0 c 1/2. This extends a recent result of Luca, Menares and Madariaga for1/4≤ c ≤1/2. We also pose two conjectures for further research.  相似文献   

4.
The Laplace-Stieltjes transform of the variance function V(y) = var (N(0, y]) for the number N(0, y] of departures in a time interval of length y is found for stationary M/G/1 and G1/M/1 queueing systems. It is shown that for G1/M/1 systems V(y) is linear only for M/M/1.  相似文献   

5.
An n-dimensional form of Winternitz's Theorem for convex sets in En can be related to a standard inequality for e. The object of this note is to prove two inequalities for n-dimensional simplexes that can be related to the basic inequalities (1+1/n)n < e < (1+1/n)n+1.The author wishes to thank Leon Gerber, St. John's University for his beneficial suggestions.  相似文献   

6.
该文讨论如下具有奇异系数的反应扩散方程组Cauchy问题非负局部解的存在性和不存 在性, 以及解在有限时间内的爆破问题(u_t-t^{-1}Δ u=α_1u^{q_1}+β_1v^\{p_1}+f_1(x),t>0,x∈R^N; v_t-t^\{-1}Δ v=α_2u^\{q_2}+β_2v^{p_2}+f_2(x),t>0,x∈R^ N;lim_{t→0+}u(t,x)=lim_{t→0+}v(t,x)=0,x∈R^N. 其中p_i>1, q_i>1 (i=1, 2) , α_1≥0, α_2>0, β_1>0, β_2≥0, f_ i(x) (i=1, 2)为连续非负有界函数, (f_1(x), f_2(x))(0, 0) . 文章给出了非负局部解存在的显式条件和非负局部解不存在的比较结果, 也得到解在有限时间爆破的一些结果.  相似文献   

7.
We consider, for maps in H1/2(S1;S1), a family of (semi)norms equivalent to the standard one. We ask whether, for such a norm, there is some map in H1/2(S1;S1) of prescribed topological degree equal to 1 and minimal norm. In general, the answer is no, due to concentration phenomena. The existence of a minimal map is sensitive to small perturbations of the norm. We derive a sufficient condition for the existence of minimal maps. In particular, we prove that, for every given norm, there are arbitrarily small perturbations of it for which the minimum is attained. In case there is no minimizer, we determine the asymptotic behavior of minimizing sequences. We prove that, for such minimizing sequences, the energy concentrates near a point of S1. We describe this concentration in terms of bubbling-off of circles.  相似文献   

8.
J.A. de la Peña 《代数通讯》2013,41(6):1795-1807
Inspired by a result in [Ga], we locate three integer forms of Fq[SL(n+ 1)] over k[q,q -1] wih a presentation by generators and relations, which for q=1 specialize to U(𝔥)), where 𝔥 is the Lie bialgebra of the Poisson Lie group dual to SL(n+1). In sight of this we prove two PBW-like theorems for Fq [SL(n+ 1)], both related to the classical PBW theorem for U(𝔥).  相似文献   

9.
In this paper we give a further investigation of the method introduced by the author in [1, Frequency-domain bounds for nonnegative unsharply band-limited functions] for proving bounds for functions with nonnegative Fourier transforms. We also dealt with the question of how large the supremum KS of all numbers |f(u)| is with f the Fourier transform of a nonnegative integrable function F and f(0) = 1, |f(ku)| ≤ ε for k ∈ S. Here u > 0 and S ⊂ {2, 3, . . .}. This problem was related in [1] to finding the infimum MS of all numbers Mh = maxϑ [(1−h(ϑ))/(1− cos ϑ)] over all 2π-periodic even, smooth functions h whose Fourier cosine coefficients ak vanish for k ∉ S, and it was proved and announced for several cases that MS (1−KS ) = 1. In this paper we prove the results announced in [1]. To that end we generalize the method given in [1] to include Fourier transforms f of probability measures on R and a certain generalized function h, and we show that the numbers KS, MS are assumed as |f(u)|, Mh for certain allowed f,h. Moreover, we establish a fundamental relation between finding the numbers KS, MS and the numbers KT, MT where T = {2, 3, . . .}\S. In particular, we show that MT = 2KS (2KS − 1)−1,KT = 1/2 MS(MS − 1)−1 and that MT (1 − KT) = 1,KSKT = 1/2 , whenever MS (1 − KS) = 1.  相似文献   

10.
We establish two new lower bounds for the halfspace range searching problem: Given a set of n points in ℝ d , where each point is associated with a weight from a commutative semigroup, compute the semigroup sum of the weights of the points lying within any query halfspace. Letting m denote the space requirements, we prove a lower bound for general semigroups of [\varOmega\tilde](n1-1/(d+1)/m1/(d+1))\widetilde{\varOmega}(n^{1-1/(d+1)}/m^{1/(d+1)}) and for integral semigroups of [\varOmega\tilde](n/m1/d)\widetilde{\varOmega}(n/m^{1/d}).  相似文献   

11.
Let χ denote a primitive, Dirichlet character to the modulus q > 1, such that χ(?1) = 1. Then it is shown that the Riemann zeta function can be expressed in terms of the non-trivial zeros of L(S, χ). Although the explicit form of the representation is given only when σ > 1, and only for χ(?1) = 1, it is indicated how similar representations can be obtained for σ > 0 when χ(?1) = ±1.  相似文献   

12.
A formation 𝔉 of finite groups has the generalized Wielandt property for residuals, or 𝔉 is a GWP-formation, if the 𝔉-residual of a group generated by two 𝔉-subnormal subgroups is the subgroup generated by their 𝔉-residuals. The main aim of the paper is to determine some su?cient conditions for a finite group to split over its 𝔉-residual.  相似文献   

13.
we study the monotonicity of certain combinations of the Gaussian hypergeometric functions F(-1/2,1/2;1;1- xc) and F(-1/2- δ,1/2 + δ;1;1- xd) on(0,1) for given 0 c 5d/6 ∞ andδ∈(-1/2,1/2),and find the largest value δ1 = δ1(c,d) such that inequality F(-1/2,1/2;1;1- xc) F(-1/2- δ,1/2 + δ;1;1- xd) holds for all x ∈(0,1). Besides,we also consider the Gaussian hypergeometric functions F(a- 1- δ,1- a + δ;1;1- x3) and F(a- 1,1- a;1;1- x2) for given a ∈ [1/29,1) and δ∈(a- 1,a),and obtain the analogous results.  相似文献   

14.
江海新  吴芸 《数学学报》2013,(1):135-144
讨论了ω,q-Bernstein多项式的Voronovskaya-型公式及其收敛的饱和性.给出了当01[0,1]时ω,q-Bernstein多项式的Voronovskaya-型公式.如果0<ω,q<1,f∈C1[0,1]时ω,q-Bernstein多项式的Voronovskaya-型公式.如果0<ω,q<1,f∈C1[0,1],则ω,q-Bernstein多项式的收敛阶为o(q1[0,1],则ω,q-Bernstein多项式的收敛阶为o(qn)当且仅当((f(1-qn)当且仅当((f(1-q(k-1)-f(1-q)(k-1)-f(1-q)k))/((1-qk))/((1-q(k-1)-(1-q(k-1)-(1-qk)))=f'(1-qk)))=f'(1-qk),k=1,2,…还证明f如果f在[0,1]是凸的或者在(-ε,1+ε)(ε>0)解析,则ω,q-Bernstein多项式的收敛阶为o(qk),k=1,2,…还证明f如果f在[0,1]是凸的或者在(-ε,1+ε)(ε>0)解析,则ω,q-Bernstein多项式的收敛阶为o(qn)当且仅当f是线性函数.  相似文献   

15.
This paper deals with 2-player zero-sum repeated games in which player 1 receives a bonus at stage t if he repeats the action he played at stage t−1. We investigate the optimality of simple strategies for player 1. A simple strategy for player 1 consists of playing the same mixed action at every stage, irrespective of past play. Furthermore, for games in which player 1 has a simple optimal strategy, we characterize the set of stationary optimal strategies for player 2.  相似文献   

16.
Variable-weight optical orthogonal code (OOC) was introduced by Yang for multimedia optical CDMA systems with multiple quality of service requirements. It is proved that optimal (v, {3, 4}, 1, (1/2, 1/2))-OOCs exist for some complete congruence classes of v. In this paper, for ${Q \in \{(1/3, 2/3), (2/3, 1/3)\}}$ , by using skew starters, it is also proved that optimal (v, {3, 4}, 1, Q)-OOCs exist for some complete congruence classes of v.  相似文献   

17.
The paper refines and supplements some classical and modern distortion theorems for functions regular in the disk |z| < 1 and satisfying the condition |f(z)| < 1 for |z| < 1. Distortion bounds at points of the disk |z| < 1 and also on its boundary |z| = 1, provided that |f(z)| = 1, are considered both for univalent and multivalent mappings. Bibliography: 22 titles. __________ Translated from Zapiski Nauchnykh Seminarov POMI, Vol. 350, 2007, pp. 26–39.  相似文献   

18.
Full Ideals     
Contractedness of 𝔪-primary integrally closed ideals played a central role in the development of Zariski's theory of integrally closed ideals in two-dimensional regular local rings (R, 𝔪). In such rings, the contracted 𝔪-primary ideals are known to be characterized by the property that I: 𝔪 = I: x for some x ∈ 𝔪 ?𝔪2. We call the ideals with this property full ideals and compare this class of ideals with the classes of 𝔪-full ideals, basically full ideals, and contracted ideals in higher dimensional regular local rings. The 𝔪-full ideals are easily seen to be full. In this article, we find a sufficient condition for a full ideal to be 𝔪-full. We also show the equivalence of the properties full, 𝔪-full, contracted, integrally closed, and normal, for the class of parameter ideals. We then find a sufficient condition for a basically full parameter ideal to be full.  相似文献   

19.
We investigate the weighted bounds for multilinear maximal functions and Calderón–Zygmund operators from \(L^{p_1}(w_1)\times \cdots \times L^{p_m}(w_m)\) to \(L^{p}(v_{\vec {w}})\), where \(1<p_1,\cdots ,p_m<\infty \) with \(1/{p_1}+\cdots +1/{p_m}=1/p\) and \(\vec {w}\) is a multiple \(A_{\vec {P}}\) weight. We prove the sharp bound for the multilinear maximal function for all such \(p_1,\ldots , p_m\) and prove the sharp bound for \(m\)-linear Calderón–Zymund operators when \(p\ge 1\).  相似文献   

20.
A generalized balanced tournament design, GBTD(n, k), defined on a kn-set V, is an arrangement of the blocks of a (kn, k, k – 1)-BIBD defined on V into an n × (kn – 1) array such that (1) every element of V is contained in precisely one cell of each column, and (2) every element of V is contained in at most k cells of each row. Suppose we can partition the columns of a GBTD(n, k) into k + 1 sets B1, B2,..., Bk + 1 where |Bi| = n for i = 1, 2,..., k – 2, |Bi| = n–1 for i = k – 1, k and |Bk+1| = 1 such that (1) every element of V occurs precisely once in each row and column of Bi for i = 1, 2,..., k – 2, and (2) every element of V occurs precisely once in each row and column of Bi Bk+1 for i = k – 1 and i = k. Then the GBTD(n, k) is called partitioned and we denote the design by PGBTD(n, k). The spectrum of GBTD(n, 3) has been completely determined. In this paper, we determine the spectrum of PGBTD(n,3) with, at present, a fairly small number of exceptions for n. This result is then used to establish the existence of a class of Kirkman squares in diagonal form.  相似文献   

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