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1.
Let A be a j x d (0,1) matrix. It is known that if j = 2k - 1 is odd, then det(AAT) ≤ (j+1)((j+1)d/4j)j; if j is even, then det(AAT) ≤ (j+1)((j+2)d/4(j+1))j. A is called a regular D-optimal matrix if it satisfies the equality of the above bounds. In this note, it is proved that if j = 2k - 1 is odd, then A is a regular D-optimal matrix if and only if A is the adjacent matrix of a (2k - 1, k, (j + l)d/4j)-BIBD; if j = 2k is even, then A is a regular D-optimal matrix if and only if A can be obtained from the adjacent matrix B of a (2k + 1,k + 1,(j + 2)d/4(j +1))-BIBD by deleting any one row from B. Three 21 x 42 regular D-optimal matrices, which were unknown in [11], are also provided.  相似文献   

2.
一、利用“性胶”求扭值. 例1求x〔〔0.,l〕s月,/(二),x“+(2一6a)x+sa,的最小位,刀将得到的最小值看作是。的函数g(。).洲出它的图象. 解厂整理:/(二)盖〔,一(3a一1)〕’一6a“+6a一1. 设j(x)在x〔〔。,幻内鼓小值为夕.”势“3一<。,“·:·泣{J·<{.在。(二、1讨、,f(二)是增区数(图l)…g二f(0)=3。“2’)当:、,a一<,,尽},;‘·<:竹寸.口J、二工一3。一1时j(x)最刁、(图2),所以夕=f(3。一l)二一6。“+〔a气l3‘)当s。一J):。JJ。);时,在。《二<,;”:j、,) O是减函数(图3).所以g=l(l)=3。“一助+3二:(。一l)“ l龙{此得 3(。一)2g(a)=一…  相似文献   

3.
Let R be a ring with 1, I be a nilpotent subring of R (there exists a natural number n, such that In = 0), and I be generated by {xj |j ∈ J} as ring. Write U = 1 + I, and it is a nilpotent group with class ≤ n - 1. Let G be the subgroup of U which is generated by {1 + xj|j ∈ J}. The group constructed in this paper indicates that the nilpotency class of G can be less than that of U.  相似文献   

4.
Let(z_(11),..., z_(1N),..., z_(m1),..., z_(mN), w_(11),..., w_(mm)) be the coordinates in C~(mN) +m~2. In this note we prove the analogue of the Theorem of Moser in the case of the real-analytic submanifold M defined as follows W = ZZ~t+ O(3),where W = {w_(ij)}_(1≤i,j≤m)and Z = {z_(ij) }_(1≤i≤m, 1≤j≤N). We prove that M is biholomorphically equivalent to the model W = ZZ~t if and only if is formally equivalent to it.  相似文献   

5.
1.已知函数f(劝的定义域是全体实数,对任意的实数二,,二2成立等式:j(Xl) f(‘2)一Zf(兰工护)·厂(芒卫云些),且了(1)=。j(x)不恒等于0.求证(1) (2) (3)f(二)是周期为2二的周期函数f(x)是偶函数成立f(Zx)二2[.l(“)〕“一12.证明含参数t其中黔铸一:奥行三鱼,所表示昨02“2 一一 yd︷r口 一 戈.宁一一r口 程 方 线 直 的五热 一一al一仇一切直线经过同一点的充要条件是212 一一叙一73试证。。53粤 l 。。53弩 cOS3(本题由沈阳杨锦生提出)‘解方程{x(x“ 6夕2)=2401夕(3x“ 2夕“)=17155没“‘>O(f=1.2.二心求证当。》2时 (本题由甘肃天…  相似文献   

6.
(xl+灰功)叮一”一1一(xz+k2夕z)宁2月一1奋1一kl(11)、.子、.,119曰‘r飞了叮、本文介绍由递归方程组 fx,=ax,一l+bg,一1 ,夕,=cx二一:+内,一1 (a、b、‘、J为常数)给出的数列{x二}、{夕,}的通项的求法. (一)基本理论 如果b、。同时为O,则易得 x,=a’一’x,,夕。=己一’夕1(3) 如果b、。不同时为0,不妨设;。手O,则 (l)+乏x(2)得 x。+kv,=(a+c走)。,一1+(b+dk)夕。- (IQ)、(川即是数列{x,}、{g。}的通项公式.但它们形式过繁,.有必要将其化简.注意到x:、gl为初值(常数),而k:、棍可由a、b、.。、d唯一确定,因而也为常数.由此可知,数列{x,}、…  相似文献   

7.
In this paper,we prove the existence of quasi-periodic solutions and the boundedness of all the solutions of the general semilinear quasi-periodic differential equation x′′+ax~+-bx~-=G_x(x,t)+f (t),where x~+=max{x,0},x~-=max{-x,0},a and b are two different positive constants,f(t) is C~(39) smooth in t,G(x,t)is C~(35) smooth in x and t,f (t) and G(x,t) are quasi-periodic in t with the Diophantine frequency ω=(ω_1,ω_2),and D_x~iD_t~jG(x,t) is bounded for 0≤i+j≤35.  相似文献   

8.
J目.J.J不‘孟‘‘斌.,,邵汤气r日了梦孙、叮弓七』:卜.J今JJ‘2〔一’考虑边值问题 g:,,,口“子_‘。八口“u、口f,,.八口u、._,__、__,,__、 龟去‘二贡t乞气叭万)介方一j一兰一lb〔x)芒井}+c‘二):=厂(x),0蕊x(l, 1口x‘\口x‘,口x\口x/ 才‘,_日U_。、,,,_八1 了“二卫二一“O。当x=0 .1。 又口x‘一‘这里a(x)任C“(〔0,l」),西(x)任C‘(〔0,l]),C(x扩(x)任C“(巨0,l〕),a(x))a。>0,。。几级一‘数,b(x),c(x))0.试给出并证明和它相应的极小位能原理.(20分)二、试确定求积公式 J{。,‘X)dX澎‘{·,(一,卜。,(。卜·,(、)}中的系数…  相似文献   

9.
Let $-1=x_{n,n}相似文献   

10.
Define two operators In and It,the inner product operator In(g)(x) := j∈Zs(g,f(·-j))f(x-j) and the interpolation operator It(g)(x) := j∈Zs g(j)f(x-j),where f belongs to some space and integer s 1.We call f the generator of the operators In and It.It is well known that there are many results on operators In and It.But there remain some important problems to be further explored.For application we first need to find the available generators (that can recover polynomials as It(p) = p or In(p) = p,p ∈Πm-1) for constructing the relative operators.In this paper,we focus on the available generator in the class of spline functions.We shall see that not all spline functions can be used to construct available generators.Fortunately,we do find a spline function in S,of degree m-1,where m is even and S is a class of splines.But for odd m the problem is still open.Results on spline functions in this paper are new.  相似文献   

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