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71.
Assume X is a normed space, every x* ∈ S(X*) can reach its norm at some point in B(X), and Y is a β-normed space. If there is a quotient space of Y which is asymptotically isometric to lβ, then L(X, Y) contains an asymptotically isometric copy of lβ. Some sufficient conditions are given under which L(X, Y) fails to have the fixed point property for nonexpansive mappings on closed bounded β-convex subsets of L(X, Y). 相似文献
72.
We present here some results on the applications of linear recursive sequences of order $2$ to the Fermat pseudoprimes, Fibonacci pseudoprimes, and Dickson pseudoprimes. 相似文献
73.
Recursive fault-tolerance of Fibonacci cube in hypercubes 总被引:1,自引:0,他引:1
Petr Gregor 《Discrete Mathematics》2006,306(13):1327-1341
Fibonacci cube is a subgraph of hypercube induced on vertices without two consecutive 1's. If we remove from Fibonacci cube the vertices with 1 both in the first and the last position, we obtain Lucas cube. We consider the problem of determining the minimum number of vertices in n-dimensional hypercube whose removal leaves no subgraph isomorphic to m-dimensional Fibonacci cube. The exact values for small m are given and several recursive bounds are established using the symmetry property of Lucas cubes and the technique of labeling. The relation to the problem of subcube fault-tolerance in hypercube is also shown. 相似文献
74.
利用矩阵对的商奇异值分解,给出了线性流形上矩阵方程AXAT=B存在极小Frobe- nius范数对称正交对称解的充要条件及其解的表达式. 相似文献
75.
Yunkai Zhou 《Numerical Linear Algebra with Applications》2006,13(8):621-642
We study Davidson‐type subspace eigensolvers. Correction equations of Jacobi–Davidson and several other schemes are reviewed. New correction equations are derived. A general correction equation is constructed, existing correction equations may be considered as special cases of this general equation. The main theme of this study is to identify the essential common ingredient that leads to the efficiency of a diverse form of Davidson‐type methods. We emphasize the importance of the approximate Rayleigh‐quotient‐iteration direction. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
76.
关于G-M成果研究的若干新动态Ⅰ——G-M型空间的若干品种 总被引:1,自引:1,他引:0
结合自己的工作,对Gowers-Maurey系列成果获Fields奖以来的研究的新动态作一综述。本是上篇,主要讨论含遗传不可分解空间在内的G-M型空间的若干品种。 相似文献
77.
考察一类带有匹配不确定性的非线性系统,采用微分拓扑方法,将标称系统关于局部能控分解的结果和(f,g)-不变分布的Quaker引理推广到非线性不确定性系统. 相似文献
78.
Images of locally compact metric spaces 总被引:1,自引:0,他引:1
Li Zhaowen 《Acta Mathematica Hungarica》2003,99(1-2):81-88
We establish relationships between locally compact-metric spaces and all kinds of spaces with mk-system (compact k-network) by means of compact-covering mappings, quotient mapping and closed mappings.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
79.
K. Keremedis 《Algebra Universalis》1998,39(3-4):163-169
We show that the axiom of choice AC is equivalent to the statement Any quotient group of any abelian group has a selector. We also show that the multiple choice axiom MC is equivalent to the assertion: Any filter
in any Boolean ring
has a well ordered filterbase.
Received October 3, 1996; accepted in final form May 1, 1998. 相似文献
80.
We describe rational knots with any of the possible combinations of the properties (a)chirality, (non-)positivity, (non-)fiberedness, and unknotting number one (or higher), and determine exactly their number for a given number of crossings in terms of their generating functions. We show in particular how Fibonacci numbers occur in the enumeration of fibered achiral and unknotting number one rational knots. Then we show how to enumerate rational knots of given crossing number depending on genus and/or signature. This allows to determine the asymptotical average value of these invariants among rational knots. We give also an application to the enumeration of lens spaces. 相似文献