球上同伦群的不变量

<正> §1.设 S~(q+1)为 q+1维球.讨论同伦群 П_r(S~(q+1))时 H.Hopf,G.W.WhiteheadP.J.Hilton 等发展了广义 Hopf 不变量,H:П_r(S~(q+1))→П_r(S~(2q+1)). (1)在同伦群 П_r(S~(q+1))中,差数 r—(q+1)比 П_r(S~(2q+1))中的差数 r—(2q+1)大.在同伦群的计算中差数小的应该先计算,所以通过 Hopf不变量利用差数较小的同伦群表达差数较     

RESEARCH ANNOUNCEMENTS On Generalized D.H.Lenmer''''s Problem

If q is an odd integer, q≥3,for any integers α, (α,q) = 1,there exsits a positiveinteger α, so tbat αα≡1(mod q) and 1≤α≤q - 1. Let L(q) = {α|α∈Z,1≤α≤q - 1, (α,q) = 1 and α +α=1(mod 2)}. (1)About the property of elements of L(q) is a generalization of a problem of D. H.Lenmer ([1],p. 12). In [3], it was conjectured that     

VARIATIONS ON A THEME BY EULER

1.IntroductionAHallliltolliansystemofdifferentialequationsonRZnisgivedbyP~~H,(P,q),q=HP(P,q),(1)wherep=(pl,'.,P.),q=(ql,',q.)eR"arethegeneralizedcoordinatesandmolllentarespectivelyandH(P,q)istheellergyofthesystem.Thesystem(1)canberewrittenasthecompactf…     

充分条件和必要条件的判断

对于充分条件和必要条件 ,要能够正确地理解和判断 .1　概念1.1　若 p q ,则称p是 q的充分条件 ,q是p的必要条件 .1.2　若 p q ,则 p是q的充要条件 .1.3　若p q且 q 　q ,则称p是 q的充分不必要条件 .1.4　若 p 　q且 q p ,则称 p是q的必要不充分条件 .1.5　若p 　q且q 　 p,则称p是 q的既不充分也不必要条件 .2　概念的理解2 .1　从命题的角度理解设原命题为“若 p则q” ,则1)若原命题为真 ,则 p是q的充分条件 .2 )若逆命题为真 ,则 p是 q的必要条件 .3)若原命题和逆命题都为真 ,则p是 q的充要条件 .4 )若原命题为真而逆命题为假 ,…     

On the generalization of the D. H. Lehmer problem

Let n ≥ 2 be a fixed positive integer, q ≥ 3 and c be two integers with （n, q） = （c, q） = 1. We denote by rn（51, 52, C; q） （δ 〈 δ1,δ2≤ 1） the number of all pairs of integers a, b satisfying ab ≡ c（mod q）, 1 〈 a ≤δ1q, 1 ≤ b≤δ2q, （a,q） = （b,q） = 1 and nt（a＋b）. The main purpose of this paper is to study the asymptotic properties of rn （δ1, δ2, c; q）, and give a sharp asymptotic formula for it.     

简易逻辑中的“p或q”

在高一数学新教材中引进了简易逻辑这一节,许多同学对“p或q”这张真值表提出了质疑. 质疑1 p:1是有理数;q;1是无理数.这里p真q假,按照真值表:“p或q”为真,可“p或q;1是有理数或1是无理数”是真命题确实让人费解. 质疑2 p:同一平面内不重合的两直线平行;q:同一平面内不重合的两直线相交.这里p假q假,按照真值表:“p或q”为假,可“p或q:同一平面内不重合的两直线平行或相交”     

Sharp constants in the doubly weighted Hardy-Littlewood-Sobolev inequality

It is well known that the doubly weighted Hardy-Littlewood-Sobolev inequality is as follows,Z Rn Z Rn f(x)g(y)|x||x.y||y|dxdy6 B(p,q,,,,n)kfkLp(Rn)kgkLq(Rn).The main purpose of this paper is to give the sharp constants B(p,q,,,,n)for the above inequality for three cases:(i)p=1 and q=1;(ii)p=1 and 1q 6∞,or 1p 6∞and q=1;(iii)1p,q∞and 1p+1q=1.In addition,the explicit bounds can be obtained for the case 1p,q∞and 1p+1q1.     

一类含三角函数级数求和的极限问题

设p和q是两个互素的正整数,a=p/qπ.本文讨论了极限limn→∞1/nn∑i=1[sinia]的取值,证明了:(1)如果q为奇数,则该极限值为-q-1/2q;(2)如果q为偶数,则该极限值为-q-2/2q.     

谈谈隐含条件的解题功能

隐含条件指的是隐蔽在题设内的不易被察觉的条件,它在很多数学问题的解题过程中往往显示着不可低估的特殊作用.笔者以近几年的中考题为例介绍几种常见的功能,供同学们学习时参考. 一、导向功能 隐含条件对许多问题的求解有着明显的导向作用,先考虑隐含条件,有助于合理地选择思维方法,更加明确思维目标. 例1 实数p、q满足p2-2p-5=0,5q2 2q-1=0,求p2 1/q2的值. 分析乍看起来解此题似乎难以下笔,但注意到已知两等式中隐含着极重要的信息.当p≠1/q时,p,1/q是关于x的方程为x2-2x-5=0两实根.由根与系数的关系可得 p 1/q=2,p·1/q=-5, ∴ p2 1/q2=(p 1/q)2-2·p/q=14.     

Orthogonal graphs of characteristic 2 and their automorphisms

The (singular) orthogonal graph O(2ν + δ,q) over a field with q elements and of characteristic 2 (where ν 1, and δ = 0,1 or 2) is introduced. When ν = 1, O(2 · 1,q), O(2 · 1 + 1,q) and O(2 · 1 + 2,q) are complete graphs with 2, q + 1 and q2 + 1 vertices, respectively. When ν 2, O(2ν + δ,q) is strongly regular and its parameters are computed. O(2ν + 1,q) is isomorphic to the symplectic graph Sp(2ν,q). The chromatic number of O(2ν + δ,q) except when δ = 0 and ν is odd is computed and the group of graph automo...     

同一命题不同呈现

命题两个能够完全重合的图形,若有部分重合,则每个图形上不重合的部分的数量(线段的长度、角的度数、图形的面积)是相等的.简证因为两个图形能够完全重合,所以令两个图形的数量均为w,令重合部分的数量为p,两个图形上不重合部分的数量分别为q1和q2,∵p +q1 =w,p+q2=w,∴p+q1 =p+q2.∴q1=q2.问题得证.     

Complexity analysis of an interior point algorithm for the semidefinite optimization based on a kernel function with a double barrier term

In this paper, we establish the polynomial complexity of a primal-dual path-following interior point algorithm for solving semidefinite optimization(SDO) problems. The proposed algorithm is based on a new kernel function which differs from the existing kernel functions in which it has a double barrier term. With this function we define a new search direction and also a new proximity function for analyzing its complexity. We show that if q1 q2 1, the algorithm has O((q1 + 1) nq1+1/2(q1-q2)logn/ε)and O((q1 + 1)3q1-2q2+1/2(q1-q2)n~1/2 logn/ε) complexity results for large- and small-update methods, respectively.     

由递推式a_(n+1)=pa_n+f(n)求通项的方法

一、引子 线性递推式an+1=pan+q(p,q为常数)的启示. 常见线性递推公式an+1=pan+q(p,q为常数)求数列通项公式的基本思路是由待定系数法构造等比数列,令an+1+a=p(an+a),得a=q/p-1(p≠1),从而有an+1+q/p-1=p(an+q/p-1),数列{an+q/p-1}为等比数列,则数列通.项公式易得. 受以上解题启发,我们可以求以下相关数     

关于不分明度量空间的几个问题

本文提出了不分明 p.q.度量中的连续性条件,从而完全刻划了在[1,4]中出现的两种不分明 q.q.度量之间的关系。在此基础上,解决了不分明 q.q.度量空间的乘性问题及 Q-C_1问题,并且将著名 Urysohn’s度量化定理推广到不分明拓扑中。     

C~n中F(p,q,s)型空间上的Bergman型算子

设p0,s≥0,q+s-1,q+n-1.讨论了C~n中单位球上F(p,q,s)到本身或A(p,q,s)空间到L(p,q,s)空间上的Bergman型算子的有界性条件.     

Graphs on which a group of order pq acts edge-transitively

Let Γ be a finite simple undirected graph with no isolated vertices. Let p, q be prime numbers with p ≥ q. We complete the classification of the graphs on which a group of order pq acts edge-transitively. The results are the following. If Aut(Γ) contains a subgroup G of order pq that acts edge-transitively on Γ, then Γ is one of the following graphs: (1) pK 1,1 ; (2) pqK 1,1 ; (3) pK q,1 ; (4) qK p,1 (p q); (5) pC q (q 2); (6) qC p (p q); (7) C p (p q = 2); (8) C pq ; (9) (Z p , C) where C = {±rμ | μ∈ Z q } with q 2, q|(p-1) and r ≡ 1 ≡ r q (mod p); (10) K p,1 (p q); (11) a double Cayley graph B(G, C) with C = {1-r μ | μ∈ Z q } and r ≡ 1 ≡ r q (mod p); (12) K pq,1 ; or (13) K p,q .     

再说一道习题的研究性学习

文[1]作为“研究性学习”的案例从多角度给出了题目设p>0,q>0,p3 q3=2,求证p q≤2的多种解法.受此启发,继续探索,现从另一角度作为“研究性学习”的案例提供于此.1现用分离变量给出一种直接的证法不妨设p≤q,于是p3≤q3,由p3 q3=2得q3-1=1-p3≥0,即(q-1)(q2 q 1)=-(p3-1)=-(p-1     

SOME SUBGROUPS OF THE EXTENDED HECKE GROUPS (H)(λq)

The authors consider the extended Hecke groups H(λq) generated by T(z) =-1 / z, S(z) = -1/(z+λq) and R(z) = 1 / -z with λq = 2cos(π/q) for q ≥ 3 an integer. Inthis paper, the even subgroup He(λq), the second commutator subgroup H"(λq) and theprincipal congruence subgroups Hp(λq) of the extended Hecke groups H(λq) are studied.Also, relations between them are given.     

On the Least Prime in Some Arithmetic Progressions

Supposethatqisasufficientlylargepositiveinteger,(a,q)=1,letP(a,q)betheleastprimeinthearithmeticprogression{n=a(modq)}andxbetheDirichletcharacterofmodulusq.L(s,x)istheDirichletL-function.Everypositiveintegerqcanbeexpressedasq=qq2,q2iscubefree.Anintegerqiscalled"hasboundedcubicpart"iftheaboveq3isboundedabsolutely.Forgeneralintegerq,Heath-Brown[1]showedthatP(a,q)q5.5.Whenqisaprime,Motohashi[2]showedthat:Foranyfordpositiveintegeraandsmallpositiverealnumber>0,thereexistindnitelymanyprimesqsucht…     

The Problem of Periodic Solutions for a Class of Dynamical System（Ⅱ）

51.IntroductionLetK:R"XR"-Rbeasmoothfunctionwithi)K(q,p)isevenandstrictlyconvexinP,VqeR"lii)K(q,6)=o,VqeR".Supl>oseV=R"-Rbeasmoothfunction,t:R"-R"'(,n<)l)beaSubmersiveoperator.WIlereR",R,.arendimensionalEducli(leanspace,qeR",PeR",C(q)=(C,(q),C,(q),-.'C.,(q)).DenoteH(q,p)=K(q,p) V(q).Throughoutthispaper,weletZ(=(q,p))=6betheequilibriumpointofthefollowingsystem-ForoperatorC,wedefinethespeedoperatorofCisWhere,CisconsideredCorr,rristl1e1>rojeclionoperatorfromR"XR,,toI{.,anddf(z)…