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1.
Sn中Moebius形式为零的曲面   总被引:8,自引:0,他引:8  
《数学学报》2004,47(2):241-250
本文证明了S  相似文献   

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Rn中积分中值点取值范围的改进   总被引:16,自引:1,他引:15  
《数学的实践与认识》2004,34(4):165-169
将Rn中积分中值定理的中值点取值范围,由积分区域D上缩小到D的内部DaD上取到.  相似文献   

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It is demonstrated that, under certain conditions, a system of n nonlinear equations with n unknowns has at least 2 n solutions. Bibliography: 2 titles.  相似文献   

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Cn中点乘子集M(Dp)的一个刻划   总被引:3,自引:0,他引:3  
《数学杂志》2001,21(3):347-350
本文用Dp-Carlesor测度对Cn中的单位球B上的Dirichlet型空间Dp的点乘子集M(Dp)就p<2k的情形进行一种刻划.  相似文献   

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Let p(n) denote the partition function and let \(\Delta \) be the difference operator with respect to n. In this paper, we obtain a lower bound for \(\Delta ^2\log \root n-1 \of {p(n-1)/(n-1)}\), leading to a proof of a conjecture of Sun on the log-convexity of \(\{\root n \of {p(n)/n}\}_{n\ge 60}\). Using the same argument, it can be shown that for any real number \(\alpha \), there exists an integer \(n(\alpha )\) such that the sequence \(\{\root n \of {p(n)/n^{\alpha }}\}_{n\ge n(\alpha )}\) is log-convex. Moreover, we show that \(\lim \limits _{n \rightarrow +\infty }n^{\frac{5}{2}}\Delta ^2\log \root n \of {p(n)}=3\pi /\sqrt{24}\). Finally, by finding an upper bound for \(\Delta ^2 \log \root n-1 \of {p(n-1)}\), we establish an inequality on the ratio \(\frac{\root n-1 \of {p(n-1)}}{\root n \of {p(n)}}\).  相似文献   

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Let ${\mathcal{D}}_{n,k} $ be the family of linear subspaces of ?n given by all equations of the form $\varepsilon _1 x_{i_1 } = \varepsilon _2 x_{i_2 } = \cdot \cdot \cdot \varepsilon _k x_{i_k } ,$ for 1 ≤ < ? ? ? < i ki and $\left( {\varepsilon _1 ,...,\varepsilon _k } \right)\varepsilon \left\{ { + 1, - 1} \right\}^k $ Also let ${\mathcal{B}}_{n,k,h} $ be ${\mathcal{D}}_{n,k} $ enlarged by the subspaces $x_{j_1 } = x_{j_2 } = \cdot \cdot \cdot x_{j_h } = 0,$ for 1 ≤. The special cases ${\mathcal{B}}_{n,2,1} $ and ${\mathcal{D}}_{n,2} $ are well known as the reflection hyperplane arrangements corresponding to the Coxeter groups of type B nand D n respectively. In this paper we study combinatorial and topological properties of the intersection lattices of these subspace arrangements. Expressions for their Möbius functions and characteristic polynomials are derived. Lexicographic shellability is established in the case of ${\mathcal{B}}_{n,k,h,} 1 \leqslant h < k$ , which allows computation of the homology of its intersection lattice and the cohomology groups of the manifold $\begin{gathered} {\mathcal{D}}_{n,2} \\ M_{n,k,h,} = {\mathbb{R}}^n \backslash \bigcup {{\mathcal{B}}_{n,k,h,} } \\ \end{gathered} $ . For instance, it is shown that $H^d \left( {M_{n,k,k - 1} } \right)$ is torsion-free and is nonzero if and only if d = t(k ? 2) for some $t,0 \leqslant t \leqslant \left[ {{n \mathord{\left/ {\vphantom {n k}} \right. \kern-0em} k}} \right]$ . Torsion-free cohomology follows also for the complement in ?nof the complexification ${\mathcal{B}}_{n,k,h}^C ,1 \leqslant h < k$ .  相似文献   

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给出数列(n)/(n)/(n!)极限的八种灵活新颖的求解方法,进一步讨论了它的教学价值.  相似文献   

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In this paper, we discuss the pairs (f, h) of arithmetical functions satisfying the functional equation in the title, whereF is the product off andh under the Dirichlet convolution; that is,F(n) = Σ d|n ?(d)h(n/d) andS(m n) = Σd|(m, n) ?(d)h(n/d). The well-known Hölder's identity is a special case of this functional equation (?(n) =n, h(n) = μ(n)). We also generalize the functional equation in the title to any arbitrary regular arithmetical convolution and discuss the pairs of solutions (f, h) of the generalized functional equation and pose some problems relating to the characterization of all pairs of solutions.  相似文献   

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In this note, we show how the algebra of n×n matrices over a field can be generated by a pair of matrices A B, where A is an arbitrary nonscalar matrix and B can be chosen so that there is the maximum degree of linear independence between the higher commutators of B with A.  相似文献   

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We establish the asymptotic distribution of the set of natural numbers in the interval [1, x] relatively prime to the corresponding value of an additive arithmetic function. The bibliography contains seven references.Translated from Mathematicheskie Zametki, Vol. 11, No. 3, pp. 259–268, March, 1972.  相似文献   

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