NA列加权乘积和的完全收敛性

本文讨论了NA和几类加权部分和及加权乘积和的完全收敛性，其中部分结果要优于iid列的已知结论。     

强平稳NA列的乘积和过程的弱收敛性

得到了强平稳NA列的乘积和过程的弱收敛性。     

NOD随机变量阵列加权乘积和的强极限定理

本文研究了行为NOD随机变量阵列加权乘积和的完全收敛性和强稳定性,推广和改进了文献[1]和[2]在NA情形时的结果以及[4]在独立同分布情形时的结果.     

不同分布NA列乘积和的强收敛性

推广了Chow等人关于不同分布的r.v.列部分和强收敛的部分结果。得到了不同分布NA列乘积和强收敛的若干充分条件。     

NOD随机变量阵列加权乘积和的完全收敛性

利用NOD随机变量的性质,研究了行为NOD随机变量阵列加权乘积和的完全收敛性,获得了一些新的结果,所得的结果推广和改进了已知的一些文献中的一系列结果.     

两两NQD阵列加权乘积和的完全收敛性和强大数定律

利用截尾法和两两NQD列部分和矩不等式,得到了两两NQD阵列加权乘积和的强大数定律,并在h-可积条件下给出了其完全收敛性的一个充分条件.     

NA随机变量加权和的收敛性

利用Rosenthal型最大值不等式,得到了NA随机变量加权和的Marcinkiewicz-Zygmund强大数定律和完全收敛性,所获结果推广和改进了一些文献中相应的结果.     

一类两两NQD列乘积和的Jamison型强稳定性

研究了一类不同分布两两NQD列的Jamison型加权乘积和的强稳定性,推广了不同分布独立列部分和与同分布NQD列部分和情形相类似的结论.     

关于两两PQD列的Jamison型加权乘积和的强稳定性及乘积和的Marcinkiewicz型强大数律

本文讨论了不同分布两两PQD列的Jamison型加权部分和加权乘积和的强稳定性，讨论了它们的部分和与乘积和的Marcinkiewicz型强大数律，改进、推广了Jamison等（1965），Etemadi(1983），Birkel(1989）的相应结果。     

关于不同分布两两NQD列的Jamison型加权乘积和的强稳定性

本文讨论了不同分布两两NQD列的Jamison型加权乘积和的强稳定性及乘积和的Marcinkiewicz型强大数律,推广并改进了Etemadi[1]关于不同分布两两独立列部分和的工作及Matula[2],王岳宝等[3]关于同分布两两NQD列部分和的工作.     

随机变量序列乘积和的矩完全收敛性

利用王岳宝等将乘积和转化为部分和的乘积之和的方法,研究了随机变量序列乘积和的矩完全收敛性,获得了乘积和矩完全收敛的充分条件.     

正相协列乘积和的重对数律与强大数律

证明了强平稳正相协列乘积和的重对数律与不同分布正相协列乘积和的强大数律,指出了部分和服从强大数律但乘积和未必服从强大数律这一事实,并讨论了定理2中一个条件的必要性．     

Productive Coreflective Classes in Top

If sequential cardinals do not exist then every topological space is generated from a converging sequence by using finite products, disjoint sums and quotients. The author acknowledges the support of the grants MSM 0021620839 and GAČR 201/06/0933 of Czech Republic.     

边界可约的Heegaard分解

本文证明了任意边界可约流形的Heegaard分解都是n个不可约的、边界不可约的三维流形的Heegaard分解通过连通和、边界连通和及边界自连通和运算而得到.     

On Cochrane sums over short intervals

The main purpose of this paper is to study the mean square value problem of Cochrane sums over short intervals by using the properties of Gauss sums and Kloosterman sums, and finally give a sharp asymptotic formula.     

Exponential sum estimates over subgroups and almost subgroups of \mathbb{Z}_{Q}^{*} , where Q is composite with few prime factors

In this paper we extend the exponential sum results from [BK] and [BGK] for prime moduli to composite moduli q involving a bounded number of prime factors. In particular, we obtain nontrivial bounds on the exponential sums associated to multiplicative subgroups H of size q^δ, for any given δ > 0. The method consists in first establishing a ‘sumproduct theorem’ for general subsets A of . If q is prime, the statement, proven in [BKT], expresses simply that either the sum-set A + A or the product-set A.A is significantly larger than A, unless |A| is near q. For composite q, the presence of nontrivial subrings requires a more complicated dichotomy, which is established here. With this sum-product theorem at hand, the methods from [BGK] may then be adapted to the present context with composite moduli. They rely essentially on harmonic analysis and graph-theoretical results such as Gowers’ quantitative version of the Balog–Szemeredi theorem. As a corollary, we get nontrivial bounds for the ‘Heilbronn-type’ exponential sums when q = p^r (p prime) for all r. Only the case r = 2 has been treated earlier in works of Heath-Brown and Heath-Brown and Konyagin (using Stepanov’s method). We also get exponential sum estimates for (possibly incomplete) sums involving exponential functions, as considered for instance in [KS]. Submitted: October 2004 Revision: June 2005 Accepted: August 2005     

Riemann Zeta函数的七阶和式

通过构造一个Riemann Zeta函数ζ(k)的部分和ζ_n(k)的幂级数函数,利用牛顿二项式展开及柯西乘积公式可以计算出一些重要的和式.再将该幂级数函数由一元推广到二元甚至多元,由此得到Riemann Zeta函数的高次方和式之间的关系.并利用对数函数与第一类Stirling数之间的关系式及ζ(k)函数满足的相关等式,可得出Riemann Zeta函数的18个七阶和式,以及其它一些高次方的和式.     

Infinite class of new sign ambiguities

In 1934, two kinds of multiplicative relations, the norm and the Davenport-Hasse relations, between Gauss sums, were known. In 1964, H. Hasse conjectured that the norm and the Davenport-Hasse relations were the only multiplicative relations connecting Gauss sums over Fp. However, in 1966, K. Yamamoto provided a simple counterexample disproving the conjecture. This counterexample was a new type of multiplicative relation, called a sign ambiguity, involving a ± sign not connected to elementary properties of Gauss sums. In this paper, we give an explicit product formula involving Gauss sums which generates an infinite class of new sign ambiguities, and we resolve the ambiguous sign by using Stickelberger?s theorem.     

On complemented subspaces of sums and products of Banach spaces

It is proved that there exist complemented subspaces of countable topological products (locally convex direct sums) of Banach spaces which cannot be represented as topological products (locally convex direct sums) of Banach spaces.