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1.
麦结华  孙太祥 《中国科学A辑》2007,37(10):1221-1227
设 $G$ 是一个图, $f:G\rightarrow G$ 是连续映射. 用$R(f)$和$\Omega (f)$分别表示$f$的回归点集和非游荡集. 设$\Omega_0 (f)=G$, $\Omega_n (f)=\Omega (f|_{\Omega_{n-1} (f)})$(对任$n\in {\N}$). 满足$\Omega_{m} (f)=\Omega_{m+1} (f)$的最小的$m\in {\N}\cup \{\infty\}$称为$f$的深度. 证明了$\Omega_2(f)=\overline{R(f)}$且 $f$的深度不超过2. 进一步, 还得到$f$的非游荡点的若干性质.  相似文献   

2.
《中国科学A辑》2008,38(1):21-30
对于三维幂零流形上的所有映射, 给出了完整计算 Nielsen 型数 $NP_n(f)$ 和 $N\Phi_n(f)$ 的显式公式. 最一般的情形已被 Heath 和 Keppelmann 讨论过, 我们研究剩余的部分. 而在三维幂零流形映射的同伦最小周期集的研究中, 给出了三维幂零流形上所有映射的最小周期集的完整描述, 并包含了对Jezierski和Marzantowicz 结果的改正.  相似文献   

3.
设 $G$ 是一个简单图. 设$f$是从$V(G) \cup E(G)$到 $\{1, 2,\ldots, k\}$的一个映射.对任意的 $v\in V(G)$, 设$C_f(v)=\{f(v)\}\cup \{f (vw)|w\in V(G),vw\in E(G)\}$ . 如果 $f$ 是一个 $k$-正常全染色, 且对 $u, v\in V(G),uv\in E(G)$, 有 $C_f(u)\neq C_f(v)$, 那么称 $f$ 为$k$-邻点可区别全染色 (简记为$k$-$AVDTC$). 设  相似文献   

4.
设$u \in H(D), \ \phi$为$D$上的解析自映射,定义$H(D)$上的加权复合算子为$u C_{\phi}(f)=$$uf\circ\phi$, \ $f\in H(D)$.本文得到了从$A^{p}_{\alpha}$到$A^{\infty}(\varphi)\ (A_{0}^{\infty}(\varphi))$的加权复合算子$u C_{\phi}$的有界性和紧性的充要条件.  相似文献   

5.
研究了超越亚纯函数$f$的微分多项式$f^kQ[f]+P[f]$的零点分布. 给出了以下结果:对于满足$\delta(\infty,f)\geq1-\alpha>0$ ($\alpha$为常数, $0\leq \alpha<1$ )的超越亚纯函数$f(z)$, 若$T(r,f)=O((\log r)^2)$,则微分多项式$f^kQ[f]+P[f]$ ($Q[f]\not\equiv 0,\ P[f] \not\equiv 0$)在 可数个圆盘并集之外有无穷多个零点,其中$k>\frac{1+\Gamma_{P}+\gamma_{P}+\alpha(1+\Gamma_Q+\Gamma_{P}-\gamma_{P})} {1-\alpha }$, $\Gamma_{Q}$是$Q[f]$的权, $\Gamma_{P}$和$\gamma_{P}$是$P[f]$的权和次数.  相似文献   

6.
设函数 $\alpha(t)$在$\bf R$上非负连续 和 $1\le{p}<+{\infty}$, 则 $L_{\alpha}^p=\{f: \int_{-{\infty}}^{\infty}|f(t)e^{-\alpha(t)}|^p\mathrm{d}t<{\infty}\}$ 是Banach空间. 本文中我们得到了一个复指数函数系在$L_{\alpha}^{p}$ 空间中稠密的充分必要条件.  相似文献   

7.
$P_m\times K_n$的邻点可区别全色数   总被引:1,自引:0,他引:1       下载免费PDF全文
设 $G$ 是简单图. 设$f$是一个从$V(G)\cup E(G)$ 到$\{1, 2,\cdots, k\}$的映射. 对每个$v\in V(G)$, 令 $C_f (v)=\{f(v)\}\cup \{f(vw)|w\in V(G), vw\in E(G)\}$. 如果 $f$是$k$-正常全染色, 且对任意$u, v\in V(G), uv\in E(G)$, 有$C_f(u)\ne C_f(v)$, 那么称 $f$ 为图$G$的邻点可区别全染色(简称为$k$-AVDTC).数 $\chi_{at}(G)=\min\{k|G$ 有$k$-AVDTC\}称为图$G$的邻点可区别全色数.本文给出路$P_m$和完全图$K_n$ 的Cartesion积的邻点可区别全色数.  相似文献   

8.
图的邻点强可区别的全染色   总被引:4,自引:0,他引:4       下载免费PDF全文
设 $G(V, E)$是阶数不小于~3 的简单连通图, $k$ 是自然数, $f$ 是从~$V(G)\cup E(G)$到 ~$\{1, 2, \dots, k\}$ 的映射, 满足: 对任意的 ~$uv\inE(G),f(u)\not= f(v), f(u)\not= f(uv)\not= f(v)$; 对任意的$uv,uw\in E(G)\,(v\neq w), f(uv)\neq f(uw)$; 对任意的$uv\in E(G), C(u)\neq C(v)$, 其中$C(u)=\{f(u)\}\cup \{f(v)|uv\in E(G)\}\cup \{f(uv)|uv\in E(G)\}$, 则称$f$是图$G$ 的一个邻点强可区别的全染色法. 简记作 $k$-AVSDTC, 且称 $ \chi_{\rm ast}(G)=\min\{k\mid G \textrm{ 的所有 }\ k\textrm{-AVSDTC}\} $ 为$G$ 的邻点强可区别的全色数. 得到了圈、完全图、完全二部图、树的邻点强可区别全色数.  相似文献   

9.
设f:M→M是准幂零流形M上的连续自映射,N(f)是f的渐近Nielsen数.本文应用Nielsen不动点理论,给出log N(f)是f的同伦类中所有映射的拓扑熵的下确界的一个充要条件,该结果是关于幂零流形上类似结果的一个本质推广.  相似文献   

10.
该文讨论了二阶三点边值问题$-u'(t)=b(t)f(u(t))$满足$u'(0)=0$, $u(1)={\alpha}u({\eta})$ 正解的存在性与多重性, 其中常数$\alpha, \eta\in(0,1)$, $f\in C ([0,\infty),[0,\infty) )$, $b\in C ([0,1],[0,\infty) )$且存在$t_0\in[0,1]$使$b(t_0)>0$. 利用该问题相应的Green函数, 将其转化为Hammerstein型积分方程, 借助于锥上的不动点指数理论,给出了该问题单个正解和多个正解存在的与其相应线性问题的第一特征值有关的最佳充分性条件.  相似文献   

11.
In this paper, we study the uniqueness of meromorphic functions that share two small functions with their derivatives. We prove the following result: Let $f$ be a nonconstant meromorphic function such that $\mathop {\overline{\lim}}\limits_{r\to\infty} \frac{\bar{N}(r,f)}{T(r,f)}<\frac{3}{128}$, and let $a$, $b$ be two distinct small functions of $f$ with $a\not\equiv\infty$ and $b\not\equiv\infty$. If $f$ and $f"$ share $a$ and $b$ IM, then $f\equiv f"$.  相似文献   

12.
设$W_{\beta}(x)=\exp(-\frac{1}{2}|x|^{\beta})~(\beta > 7/6)$ 为Freud权, Freud正交多项式定义为满足下式$\int_{- \infty}^{\infty}p_{n}(x)p_{m}(x)W_{\beta}^{2}(x)\rd x=\left \{ \begin{array}{ll} 0 & \hspace{3mm} n \neq m , \\ 1 & \hspace{3mm}n = m \end{array} \right.$的  相似文献   

13.
Let β 〉 0 and Sβ := {z ∈ C : |Imz| 〈β} be a strip in the complex plane. For an integer r ≥ 0, let H∞^Г,β denote those real-valued functions f on R, which are analytic in Sβ and satisfy the restriction |f^(r)(z)| ≤ 1, z ∈ Sβ. For σ 〉 0, denote by Bσ the class of functions f which have spectra in (-2πσ, 2πσ). And let Bσ^⊥ be the class of functions f which have no spectrum in (-2πσ, 2πσ). We prove an inequality of Bohr type
‖f‖∞≤π/√λ∧σ^r∑k=0^∞(-1)^k(r+1)/(2k+1)^rsinh((2k+1)2σβ),f∈H∞^r,β∩B1/σ,
where λ∈(0,1),∧and ∧′are the complete elliptic integrals of the first kind for the moduli λ and λ′=√1- λ^2,respectively,and λ satisfies
4∧β/π∧′=1/σ.
The constant in the above inequality is exact.  相似文献   

14.
In this paper, some approximation formulae for a class of convolution type double singular integral operators depending on three parameters of the type(T_λf)(x, y) = ∫_a~b ∫_a~b f(t, s)K_λ(t-x,s-y)dsdt, x,y ∈(a,b), λ∈Λ  [0,∞),(0.1)are given. Here f belongs to the function space L_1( a,b ~2), where a,b is an arbitrary interval in R. In this paper three theorems are proved, one for existence of the operator(T_λf)(x, y) and the others for its Fatou-type pointwise convergence to f(x_0, y_0), as(x,y,λ) tends to(x_0, y_0, λ_0). In contrast to previous works, the kernel functions K_λ(u,v)don't have to be 2π-periodic, positive, even and radial. Our results improve and extend some of the previous results of [1, 6, 8, 10, 11, 13] in three dimensional frame and especially the very recent paper [15].  相似文献   

15.
Let G be a graph with vertex set V(G) and edge set E(G). A labeling f : V(G) →Z2 induces an edge labeling f*: E(G) → Z2 defined by f*(xy) = f(x) + f(y), for each edge xy ∈ E(G). For i ∈ Z2, let vf(i) = |{v ∈ V(G) : f(v) = i}| and ef(i) = |{e ∈ E(G) : f*(e) =i}|. A labeling f of a graph G is said to be friendly if |vf(0)- vf(1)| ≤ 1. The friendly index set of the graph G, denoted FI(G), is defined as {|ef(0)- ef(1)|: the vertex labeling f is friendly}. This is a generalization of graph cordiality. We investigate the friendly index sets of cyclic silicates CS(n, m).  相似文献   

16.
1.IntroductionandResultsConsidernon-homogeneouslineardifferentialequationsoftheform1.Lameprovedin[7]TheoremA.LetB(z),PO(z),PI(z)*06epolynomialssuchthatdegB=n21,degPO=p<(n k)/kandH=PI(z)epo('),then(a)IfdegPI相似文献   

17.
Based on [3] and [4],the authors study strong convergence rate of the k_n-NNdensity estimate f_n(x)of the population density f(x),proposed in [1].f(x)>0 and fsatisfies λ-condition at x(0<λ≤2),then for properly chosen k_nlim sup(n/(logn)~(λ/(1 2λ))丨_n(x)-f(x)丨C a.s.If f satisfies λ-condition,then for propeoly chosen k_nlim sup(n/(logn)~(λ/(1 3λ)丨_n(x)-f(x)丨C a.s.,where C is a constant.An order to which the convergence rate of 丨_n(x)-f(x)丨andsup 丨_n(x)-f(x)丨 cannot reach is also proposed.  相似文献   

18.
Let S_s*be the class of normalized functions f defined in the open unit■such that the quantity zf’(z)/f(z)lies in an eight-shaped region in the right-half plane and satisfies the condition■.In this paper,we aim to investigate Toeplitz determinants for the inverse of this function classes S_s*associated with sine function.  相似文献   

19.
It is discussed in this paper that under what conditions, for a continuous domain L, there is a Scott continuous self-mapping f : L → L such that the set of fixed points fix(f) is not continuous in the ordering induced by L. For any algebraic domain L with a countable base and a smallest element, the problem presented by Huth is partially solved. Also, an example is given and shows that there is a bounded complete domain L such that for any Scott continuous stable self-mapping f, fix(f) is not the retract of L.  相似文献   

20.
The paper proves on the basis of [1] the following theorem: Let $\[f(z)\]$ be an entire function of lower order $\[\mu < \infty \]$, and $\[{a_i}(z)(l = 1,2, \cdots ,k)\]$ be meromorphic functions which satisfy $\[T(r,{a_i}(z)) = o\{ T(r,f)\} \]$. If $$\[\sum\limits_{i = 1}^k {\delta ({a_i}(z),f) = 1\begin{array}{*{20}{c}} {({a_i}(z) \ne \infty )}&{(1)} \end{array}} \]$$ then the deficiencies $\[\delta ({a_i}(z),f)\]$ are equal to $\[\frac{{{n_1}}}{\mu }\]$, where $\[{n_i}\]$ is an integer,$\[l = 1,2, \cdots ,k\]$.  相似文献   

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