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1.
Let \({q\geqq2}\) be an integer and denote S(n) the sum of the digits in base q of the positive integer n. Our main result is to estimate the sum \({\Sigma_{n\leqq x}\tilde{\omega}(n)}\) where \({\tilde{\omega}(n)}\) is the number of distinct prime factors p of n such that \({S(p) \equiv a \,{\rm mod} \,b \,(a \in \mathbb{Z}, b\geqq 2)}\) .  相似文献   

2.
По определению после довательность {μ n пр инадлежит классуG s , если звезда М иттагЛеффлера произвольного степе нного ряда (1) $$\mathop \sum \limits_0^\infty a_n z^n , \mathop {lim sup}\limits_{n \to \infty } \left| {a_n } \right|^{1/n}< \infty $$ , совпадает со звёздам и Миттаг-Леффлера сте пенных рядов $$\mathop \sum \limits_0^\infty \mu _n a_n z^n ,\mathop \sum \limits_0^\infty \mu _n^{ - 1} a_n z^n $$ . В работе установлены следующие утвержден ия Теорема 1.Для произво льной последователь ности ? n с условиями $$0< \varphi _n< 1,\mathop {lim}\limits_{n \to \infty } \varphi _n = 0,\mathop {lim}\limits_{n \to \infty } \varphi _n^{1/n} = 1$$ существует неубываю щая функция χ(t) такая, ч то моменты \(\mu _n = \int\limits_0^1 {t^n d\chi (t)} \) удовлетворяют условию 0<μnn звезда М иттаг-Леффлера любог о ряда (1) совпадает со звездой МиттагЛеффлера степенных рядов . Теорема 2. Для произвол ьной неотрицательно й последовательности {аn} с условием {a n } и для любой последов ательности {?n} для к оторой 0n<1, \(\mathop {\lim }\limits_{n \to \infty } \varepsilon _n = 0\) сущест вуютπ={π n }∈G s и последовательнос ть {пi} такие, что anμn≦1 (n≧n0), \(a_{n_i } \mu _{\mu _i } \geqq exp( - \varepsilon _{n_i } )\) (i=1, 2, ...) и при эmom звезда Миттаг-Леффлера ряда (1) совпа дает со звездой Миттаг- Леффлера степенных р ядов .  相似文献   

3.
If m ∈ ?, ? m is the additive group of the modulo m residue classes, $\mathcal{A} \subset \mathbb{Z}_m$ and n ∈ ?, ? m , then let $R\left( {\mathcal{A},n} \right)$ denote the number of solutions of a+a′ = n with $a,a' \in \mathcal{A}$ . The variation $V(\mathcal{A}) = \mathop {\max }\limits_{n \in \mathbb{Z}_m } |R(\mathcal{A},n + 1) - R(\mathcal{A},n)|$ is estimated in terms of the number of a’s with $a - 1 \notin \mathcal{A}$ , $a \in \mathcal{A}$ .  相似文献   

4.
A. A. Irmatov 《Acta Appl Math》2001,68(1-3):211-226
Two approaches on estimating the number of threshold functions which were recently developed by the author are discussed. Let P(K,n) denote the number of threshold functions in K-valued logic. The first approach establishes that $$P(K,n + 1) \geqslant \frac{1}{2}\left( {\mathop {K^{n - 1} }\limits_{\left\lfloor {n - 4 - 2\frac{n}{{\log _K n}}} \right\rfloor } } \right)P\left( {K,\left\lfloor {{\text{2}}\frac{n}{{\log _K n}} + 3} \right\rfloor } \right).$$ The key argument of investigation is the generalization of the result of Odlyzko on subspaces spanned by random selections of ±1-vectors. Let $E_K = \{ 0,1 \ldots ,K - 1\} $ and let E denote the set of all vectors $w_i ,i = 1, \ldots ,K^n $ , which have the form $(1,a_1 , \ldots ,a_n ),a_i \in E_K $ . Denote by $\Lambda _n (K)$ the number of all collections of different vectors $(w_{i_1 } , \ldots ,w_{i_n } ),2 \leqslant i_1 , \ldots ,i_n \leqslant \mathbb{K}^n $ , such that, for any k, $1 \leqslant k \leqslant n$ , the vector $w_{i_k } $ is minimal among all vectors from the set $E \cap {\text{span}}(w_{i_k } , \ldots ,w_{i_n } )$ . The second approach is based on topology-combinatorical techniques and allows to establish the following inequality $P(K,n) \geqslant 2\Lambda _n (K)$ .  相似文献   

5.
A partial orthomorphism of ${\mathbb{Z}_{n}}$ is an injective map ${\sigma : S \rightarrow \mathbb{Z}_{n}}$ such that ${S \subseteq \mathbb{Z}_{n}}$ and ??(i)?Ci ? ??(j)? j (mod n) for distinct ${i, j \in S}$ . We say ?? has deficit d if ${|S| = n - d}$ . Let ??(n, d) be the number of partial orthomorphisms of ${\mathbb{Z}_{n}}$ of deficit d. Let ??(n, d) be the number of partial orthomorphisms ?? of ${\mathbb{Z}_n}$ of deficit d such that ??(i) ? {0, i} for all ${i \in S}$ . Then ??(n, d) =???(n, d)n 2/d 2 when ${1\,\leqslant\,d < n}$ . Let R k, n be the number of reduced k ×?n Latin rectangles. We show that $$R_{k, n} \equiv \chi (p, n - p)\frac{(n - p)!(n - p - 1)!^{2}}{(n - k)!}R_{k-p,\,n-p}\,\,\,\,(\rm {mod}\,p)$$ when p is a prime and ${n\,\geqslant\,k\,\geqslant\,p + 1}$ . In particular, this enables us to calculate some previously unknown congruences for R n, n . We also develop techniques for computing ??(n, d) exactly. We show that for each a there exists??? a such that, on each congruence class modulo??? a , ??(n, n-a) is determined by a polynomial of degree 2a in n. We give these polynomials for ${1\,\leqslant\,a\,\leqslant 6}$ , and find an asymptotic formula for ??(n, n-a) as n ?? ??, for arbitrary fixed a.  相似文献   

6.
In the present study, we consider isometric immersions ${f : M \rightarrow \tilde{M}(c)}$ of (2n + 1)-dimensional invariant submanifold M 2n+1 of (2m + 1) dimensional Sasakian space form ${\tilde{M}^{2m+1}}$ of constant ${ \varphi}$ -sectional curvature c. We have shown that if f satisfies the curvature condition ${\overset{\_}{R}(X, Y) \cdot \sigma =Q(g, \sigma)}$ then either M 2n+1 is totally geodesic, or ${||\sigma||^{2}=\frac{1}{3}(2c+n(c+1)),}$ or ${||\sigma||^{2}(x) > \frac{1}{3}(2c+n(c+1)}$ at some point x of M 2n+1. We also prove that ${\overset{\_ }{R}(X, Y)\cdot \sigma = \frac{1}{2n}Q(S, \sigma)}$ then either M 2n+1 is totally geodesic, or ${||\sigma||^{2}=-\frac{2}{3}(\frac{1}{2n}\tau -\frac{1}{2}(n+2)(c+3)+3)}$ , or ${||\sigma||^{2}(x) > -\frac{2}{3}(\frac{1}{2n} \tau (x)-\frac{1}{2} (n+2)(c+3)+3)}$ at some point x of M 2n+1.  相似文献   

7.
Let F n be the nth Fibonacci number. The Fibonomial coefficients \(\left[ {\begin{array}{*{20}c} n \\ k \\ \end{array} } \right]_F\) are defined for nk > 0 as follows $$\left[ {\begin{array}{*{20}c} n \\ k \\ \end{array} } \right]_F = \frac{{F_n F_{n - 1} \cdots F_{n - k + 1} }} {{F_1 F_2 \cdots F_k }},$$ with \(\left[ {\begin{array}{*{20}c} n \\ 0 \\ \end{array} } \right]_F = 1\) and \(\left[ {\begin{array}{*{20}c} n \\ k \\ \end{array} } \right]_F = 0\) . In this paper, we shall provide several identities among Fibonomial coefficients. In particular, we prove that $$\sum\limits_{j = 0}^{4l + 1} {\operatorname{sgn} (2l - j)\left[ {\begin{array}{*{20}c} {4l + 1} \\ j \\ \end{array} } \right]_F F_{n - j} = \frac{{F_{2l - 1} }} {{F_{4l + 1} }}\left[ {\begin{array}{*{20}c} {4l + 1} \\ {2l} \\ \end{array} } \right]_F F_{n - 4l - 1} ,}$$ holds for all non-negative integers n and l.  相似文献   

8.
We obtain a lower bound on the number of distinct squarefree parts of the discriminants n n + (?1) n (n?1) n-1 of trinomials \({X^n - X - 1\in \mathbb{Z}[X]}\) for \({1 \leqslant n \leqslant N}\) .  相似文献   

9.
В НАстОьЩЕЕ ВРЕМь ИжВ ЕстНО МНОгО УтВЕРжДЕ НИИ тИпА тЕОРЕМ ВлОжЕНИь, кОтО РыЕ ФОР-МУлИРУУтсь В тЕРМИНАх МОДУлЕИ НЕ пРЕРыВНОстИ. ДАННАь РАБОтА сОДЕРж Ит НЕскОлькО тЕОРЕМ В лОжЕНИь с УслОВИьМИ, ВыРАжЕННы МИ В тЕРМИНАх НАИлУЧшИх п РИБлИжЕНИИE n(?,p) ФУНкц ИИ ? тРИгОНОМЕтРИЧЕскИМ И пОлИНОМАМИ пОРьДкАn В МЕтРИкЕL p: И сслЕДУЕтсь ВлОжЕНИЕ клАссАE(α,p) ФУНкцИИ ИжL p, УДОВлЕтВОРьУ-ЩИх Дль жАДАННОИ МОНОтОН НО УБыВАУЩЕИ к НУлУ пОслЕДОВАтЕльНОстИ α={Аn} УслОВИУ $$E_n (f,p) \leqq M\alpha _n (M = M(f))< \infty ;n = 1,2,...).$$ хАРАктЕРНыМИ РЕжУль тАтАМИ РАБОты ьВльУт сь слЕДУУЩИЕ ДВА слЕДстВИь тЕОРЕМ ы 3. слЕДстВИЕ 1. пУстьР≧1И Β>?1.ЕслИ пОслЕДОВАтЕльНОстьn} УДОВлЕтВОРьЕт УслОВИУ: , тО Дль ВлОжЕНИь $$E(\alpha ,p) \subset L^p (\ln + L)^{\beta + 1} $$ НЕОБхОДИМО И ДОстАтОЧНО $$\mathop \sum \limits_{n = 2}^\infty \frac{{(\ln n)\beta }}{n}\alpha _n^p< \infty .$$ слЕДстВИЕ 2.ЕслИ v>p≧1,Β≧0 И {Аn} УДОВлЕтВОРьЕт УслОВИУ (1),тО Дль ВлОжЕ НИь $$E(\alpha ,p) \subset L^\nu (\ln + L)^\beta $$ НЕОБхОДИМО И ДОстАтО ЧНО $$\mathop \sum \limits_{n = 2}^\infty n^{\nu /p - 2} (\ln + n)^\beta \alpha _n^\nu< \infty ,$$   相似文献   

10.
For the sum S of the Legendre symbols of a polynomial of odd degree n ≥ 3 modulo primes p ≥ 3, Weil’s estimate |S| ≤ (n ? 1) $ \sqrt p $ and Korobov’s estimate $$ \left| S \right| \leqslant (n - 1)\sqrt {p - \frac{{(n - 3)(n - 4)}} {4}} forp \geqslant \frac{{n^2 + 9}} {2} $$ are well known. In this paper, we prove a stronger estimate, namely, $$ \left| S \right| < (n - 1)\sqrt {p - \frac{{(n - 3)(n + 1)}} {4}} $$ .  相似文献   

11.
Let ${(\phi, \psi)}$ be an (m, n)-valued pair of maps ${\phi, \psi : X \multimap Y}$ , where ${\phi}$ is an m-valued map and ${\psi}$ is n-valued, on connected finite polyhedra. A point ${x \in X}$ is a coincidence point of ${\phi}$ and ${\psi}$ if ${\phi(x) \cap \psi(x) \neq \emptyset}$ . We define a Nielsen coincidence number ${N(\phi : \psi)}$ which is a lower bound for the number of coincidence points of all (m, n)-valued pairs of maps homotopic to ${(\phi, \psi)}$ . We calculate ${N(\phi : \psi)}$ for all (m, n)-valued pairs of maps of the circle and show that ${N(\phi : \psi)}$ is a sharp lower bound in that setting. Specifically, if ${\phi}$ is of degree a and ${\psi}$ of degree b, then ${N(\phi : \psi) = \frac{|an - bm|}{\langle m, n \rangle}}$ , where ${\langle m, n \rangle}$ is the greatest common divisor of m and n. In order to carry out the calculation, we obtain results, of independent interest, for n-valued maps of compact connected Lie groups that relate the Nielsen fixed point number of Helga Schirmer to the Nielsen root number of Michael Brown.  相似文献   

12.
Hong-Bin Chen  Wei-Tian Li 《Order》2014,31(1):137-142
Consider families of subsets of [n]:?=?{1,2,...,n} that do no contain a given poset P as a subposet. Let La(n, P) denote the largest size of such families and h(P) denote the height of P. The best known general upper bound for La(n, P) is $\left(\frac{1}{2}(|P|+h(P))-1\right)\left( \begin{array}{l}\,\,\,n \\ \lfloor \frac{n}{2} \rfloor\end{array}\right)$ , due to Bursi and Nagy (2012). This paper provides an improved upper bound $\frac{1}{m+1} \left(|P|+\frac{1}{2}(m^2+3m-2)(h(P)-1)-1\right) \left( \begin{array}{l} \,\,\,n \\ \lfloor \frac{n}{2} \rfloor\end{array}\right) $ , where m can be any positive integer less than $\lceil \frac{n}{2}\rceil$ .  相似文献   

13.
Let \(\chi _0^n = \left\{ {X_t } \right\}_0^n \) be a martingale such that 0≦Xi≦1;i=0, …,n. For 0≦p≦1 denote by ? p n the set of all such martingales satisfying alsoE(X0)=p. Thevariation of a martingale χ 0 n is denoted byV 0 n and defined by \(V(\chi _0^n ) = E\left( {\sum {_{l = 0}^{n - 1} } \left| {X_{l + 1} - X_l } \right|} \right)\) . It is proved that $$\mathop {\lim }\limits_{n \to \infty } \left\{ {\mathop {Sup}\limits_{x_0^n \in \mathcal{M}_p^n } \left[ {\frac{1}{{\sqrt n }}V(\chi _0^n )} \right]} \right\} = \phi (p)$$ , where ?(p) is the well known normal density evaluated at itsp-quantile, i.e. $$\phi (p) = \frac{1}{{\sqrt {2\pi } }}\exp ( - \frac{1}{2}\chi _p^2 ) where \int_{ - \alpha }^{x_p } {\frac{1}{{\sqrt {2\pi } }}\exp ( - \frac{1}{2}\chi ^2 )} dx = p$$ . A sequence of martingales χ 0 n ,n=1,2, … is constructed so as to satisfy \(\lim _{n \to \infty } (1/\sqrt n )V(\chi _0^n ) = \phi (p)\) .  相似文献   

14.
Let {X k,i ; i ≥ 1, k ≥ 1} be a double array of nondegenerate i.i.d. random variables and let {p n ; n ≥ 1} be a sequence of positive integers such that n/p n is bounded away from 0 and ∞. In this paper we give the necessary and sufficient conditions for the asymptotic distribution of the largest entry ${L_{n}={\rm max}_{1\leq i < j\leq p_{n}}|\hat{\rho}^{(n)}_{i,j}|}$ of the sample correlation matrix ${{\bf {\Gamma}}_{n}=(\hat{\rho}_{i,j}^{(n)})_{1\leq i,j\leq p_{n}}}$ where ${\hat{\rho}^{(n)}_{i,j}}$ denotes the Pearson correlation coefficient between (X 1,i , ..., X n,i )′ and (X 1,j ,...,X n,j )′. Write ${F(x)= \mathbb{P}(|X_{1,1}|\leq x), x\geq0}$ , ${W_{c,n}={\rm max}_{1\leq i < j\leq p_{n}}|\sum_{k=1}^{n}(X_{k,i}-c)(X_{k,j}-c)|}$ , and ${W_{n}=W_{0,n},n\geq1,c\in(-\infty,\infty)}$ . Under the assumption that ${\mathbb{E}|X_{1,1}|^{2+\delta} < \infty}$ for some δ > 0, we show that the following six statements are equivalent: $$ {\bf (i)} \quad \lim_{n \to \infty} n^{2}\int\limits_{(n \log n)^{1/4}}^{\infty}\left( F^{n-1}(x) - F^{n-1}\left(\frac{\sqrt{n \log n}}{x}\right) \right) dF(x) = 0,$$ $$ {\bf (ii)}\quad n \mathbb{P}\left ( \max_{1 \leq i < j \leq n}|X_{1,i}X_{1,j} | \geq \sqrt{n \log n}\right ) \to 0 \quad{\rm as}\,n \to \infty,$$ $$ {\bf (iii)}\quad \frac{W_{\mu, n}}{\sqrt {n \log n}}\stackrel{\mathbb{P}}{\rightarrow} 2\sigma^{2},$$ $$ {\bf (iv)}\quad \left ( \frac{n}{\log n}\right )^{1/2} L_{n} \stackrel{\mathbb{P}}{\rightarrow} 2,$$ $$ {\bf (v)}\quad \lim_{n \rightarrow \infty}\mathbb{P}\left (\frac{W_{\mu, n}^{2}}{n \sigma^{4}} - a_{n}\leq t \right ) = \exp \left \{ - \frac{1}{\sqrt{8\pi}} e^{-t/2}\right \}, - \infty < t < \infty,$$ $$ {\bf (vi)}\quad \lim_{n \rightarrow \infty}\mathbb{P}\left (n L_{n}^{2} - a_{n}\leq t \right ) = \exp \left \{ - \frac{1}{\sqrt{8 \pi}} e^{-t/2}\right \}, - \infty < t < \infty$$ where ${\mu=\mathbb{E}X_{1,1}, \sigma^{2}=\mathbb{E}(X_{1,1} - \mu)^{2}}$ , and a n  = 4 log p n ? log log p n . The equivalences between (i), (ii), (iii), and (v) assume that only ${\mathbb{E}X_{1,1}^{2} < \infty}$ . Weak laws of large numbers for W n and L n , n ≥  1, are also established and these are of the form ${W_{n}/n^{\alpha}\stackrel{\mathbb{P}}{\rightarrow} 0}\,(\alpha > 1/2)$ and ${n^{1-\alpha}L_{n}\stackrel{\mathbb{P}}{\rightarrow} 0}\,(1/2 < \alpha \leq 1)$ , respectively. The current work thus provides weak limit analogues of the strong limit theorems of Li and Rosalsky as well as a necessary and sufficient condition for the asymptotic distribution of L n obtained by Jiang. Some open problems are also posed.  相似文献   

15.
Let $\mathcal{T}_{n}$ be the semigroup of all full transformations on the finite set X n ={1,2,…,n}. For 1≤rn, set $\mathcal {T}(n, r)=\{ \alpha\in\mathcal{T}_{n} | \operatorname{rank}(\alpha)\leq r\}$ . In this note we show that, for 2≤rn?2, any maximal regular subsemigroup of the semigroup $\mathcal{T} (n,r)$ is idempotent generated, but this may not happen in the semigroup $\mathcal{T}(n, n-1)$ .  相似文献   

16.
In this paper we obtain the first non-trivial lower bound on the number of disjoint empty convex pentagons in planar points sets. We show that the number of disjoint empty convex pentagons in any set of n points in the plane, no three on a line, is at least $\left\lfloor {\tfrac{{5n}} {{47}}} \right\rfloor $ . This bound can be further improved to $\tfrac{{3n - 1}} {{28}} $ for infinitely many n.  相似文献   

17.
В работе доказываютс я следующие утвержде ния. Теорема I.Пусть ? n ↓0u \(\sum\limits_{n = 0}^\infty {\varepsilon _n^2 = + \infty } \) .Тогд а существует множест во Е?[0, 1]с μЕ=0 такое что:1. Существует ряд \(\sum\limits_{n = 0}^\infty {a_n W_n } (t)\) с к оеффициентами ¦а n ¦≦{in¦n¦, который сх одится к нулю всюду вне E и ε∥an∥>0.2. Если b n ¦=о(ε n )и ряд \(\sum\limits_{n = 0}^\infty {b_n W_n (t)} \) сх одится к нулю всюду вн е E за исключением быть может некоторого сче тного множества точе к, то b n =0для всех п. Теорема 3.Пусть ? n ↓0u \(\mathop {\lim \sup }\limits_{n \to \infty } \frac{{\varepsilon _n }}{{\varepsilon _{2n} }}< \sqrt 2 \) Тогд а существует множест во E?[0, 1] с υ E=0 такое, что:
  1. Существует ряд \(\sum\limits_{n = - \infty }^{ + \infty } {a_n e^{inx} ,} \sum\limits_{n = - \infty }^{ + \infty } {\left| {a_n } \right|} > 0,\) кот орый сходится к нулю в сюду вне E и ¦an≦¦n¦ для n=±1, ±2, ...
  2. Если ряд \(\sum\limits_{n = - \infty }^{ + \infty } {b_n e^{inx} } \) сходится к нулю всюду вне E и ¦bv¦=о(ε ¦n¦), то bn=0 для всех я. Теорема 5. Пусть послед овательности S(1)={ε 0 (1) , ε 1 (1) , ε 2 (1) , ...} u S2 0 (2) , ε 1 (2) . ε 2 (2) монотонно стремятся к нулю, \(\mathop {\lim \sup }\limits_{n \to \infty } \varepsilon ^{(i)} /\varepsilon _{2n}^{(i)}< 2,i = 1,2\) , причем \(\mathop {\lim }\limits_{n \to \infty } \varepsilon _n^{(2)} /\varepsilon _n^{(i)} = + \infty \) . Тогда для каждого ε>O н айдется множество Е? [-π,π], μE >2π — ε, которое является U(S1), но не U(S1) — множеством для тригонометричес кой системы. Аналог теоремы 5 для си стемы Уолша был устан овлен в [7].
  相似文献   

18.
Let $f(x,y,x,w) = x^2 + y^2 + z^2 + Dw^2$ , where $D >1$ is an integer such that $D \ne d^2$ and ${{\sqrt n } \mathord{\left/ {\vphantom {{\sqrt n } {\sqrt D = n^\theta , 0 < \theta < {1 \mathord{\left/ {\vphantom {1 2}} \right. \kern-0em} 2}}}} \right. \kern-0em} {\sqrt D = n^\theta , 0 < \theta < {1 \mathord{\left/ {\vphantom {1 2}} \right. \kern-0em} 2}}}$ . Let $rf(n)$ be the number of representations of n by f. It is proved that $r_f (n) = \pi ^2 \frac{n}{{\sqrt D }}\sigma _f (n) + O\left( {\frac{{n^{1 + \varepsilon - c(\theta )} }}{{\sqrt D }}} \right),$ where $\sigma _f (n)$ is the singular series, $c(\theta ) >0$ , and ε is an arbitrarily small positive constant. Bibliography: 14 titles.  相似文献   

19.
Изучается поточечна я сходимость операто ров \(\sum\limits_{n = 1}^\infty {T_n } \) Тn, где оператор связан с операторомЕ n условного математического ожи дания относительно некоторой σ-алгебры $$T_n \circ (E_n - E_{n - 1} ) = (E_n - E_{n - 1} ) \circ T_n = T_n .$$ соотношениемno(Еnn?1)=(Еnn?1)oТnn. Доказано, что огранич енностьТ n влечет пот очечную сходимость ряда \(\sum\limits_{n = 1}^\infty {T_n } \) По лученные результаты находят п рименения в исследов ании сходимости в метрикеL p рядов по системам произвoдени й некоторых систем. В ч астности, доказано, чтокаждый ряд Фурье по ортогональной сис теме Виленкина сходи тся в метрикеL p для 1<р<∞.  相似文献   

20.
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