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1.
Let G be a transitive permutation group on a set and m a positive integer. If | – | m for every subset of and all g G, then || 2mp/(p – 1) where p is the least odd prime dividing |G|. It was shown by Mann and Praeger [13] that, for p = 3, the 3-groups G which attain this bound have exponent p. In this paper we will show a generalization of this result for any odd primes.AMS Subject Classification (2000), 20BXX  相似文献   

2.
We consider Dyson's hierarchical model on a d-dimensional hierarchical lattice and define a renormalization group (RG) transformation for complex values of d as a map in the space of sequences of coupling constants determining the model Hamiltonian. We show that d=4 is a bifurcation value of this transformation for the RG transformation parameter equal to 1+2/d, and we construct a non-Gaussian RG-invariant Hamiltonian in terms of the (4–d)-expansion. We establish that the (–3/2)- and (4–d)-expansion coefficients for a non-Gaussian fixed point in the dimension d=3 have the same asymptotic representation as the size of the elementary cell tends to infinity, thus confirming that both the expansions describe the same nontrivial fixed point in the dimension three.  相似文献   

3.
Let B denote the unit ball in C n , n1, and let , , and denote the volume measure, gradient, and Laplacian respectively, with respect to the Bergman metric on B. For R and 0<p<, we denote by L p the set of real, or complex-valued measurable functions f on B for which B (1–|z|2)|f(z)| p d(z)<, and by D p the Dirichlet space of C 1 functions f on B for which | f|L p . Also, for C, we denote by X the set of C 2 real, or complex-valued functions f on B for which f=f. The main result of the paper is as follows: Let 0<p< and suppose R with –n 2. Then L p X ={0}, and for 0, D p X ={0}(a) for all n+ when p1, and(b) for all when 0<p<1.By example it is shown that the result is best possible for all values of p with pn/(n+ .  相似文献   

4.
Let (itk) (s) denote thek-th derivative of the Riemann Zeta-function,s=+it, ,t real numbers,k1 rational integers. Using ideas fromT. C. Titchmarsh and from a paper ofR. Spira, lower bounds are derived for |(itk)(s)|, |(itk)(1-s) for >1 and some infinitely many, sufficiently large values oft. Further let be an algebraic number of degreen and heightH; then a lower bound for |(itk)(its)|, dependent onn, H, k is established for alln,H1,k3, 2+7k/4 and all realt.  相似文献   

5.
Ammar Sassi  F.  Ben Amor  A. 《Potential Analysis》2002,17(1):89-103
La notion de -valeur propre de –+V sera définie pour un ouvert borné de R d ; étant une mesure dans la classe de Kato généralisée. On établira une estimation du nombre des -valeurs propres inférieures à un réel positif E.The notion of -eigenvalue of –+V will be defined for a bounded open subset of R d ; is in the generalized Kato class. An estimate for the number of -eigenvalues which are smaller then a positive real E is given.  相似文献   

6.
Given a nuclear b-space N, we show that if is a finite or -finite measure space and 1p, then the functors L loc p (,N.) and NL p (,.) are isomorphic on the category of b-spaces of L. Waelbroeck.  相似文献   

7.
A new discrete modulus of continuity is introduced for functions of boundedp-fluctuation, and direct and converse theorems are proved on the approximation of these functions by polynomials with respect to multiplicative systems. Sufficient conditions for the convergence of Fourier series with respect to multiplicative systems are also obtained and these are the best possible in a certain sense.

. 60-  相似文献   

8.
Let (Z n ) n 0 be a supercritical Galton–Watson process with finite re-production mean  and normalized limit W=lim n n Z n . Let further : [0,) [0,) be a convex differentiable function with (0)=(0)=0 and such that ( ) is convex with concave derivative for some n 0. By using convex function inequalities due to Topchii and Vatutin, and Burkholder, Davis and Gundy, we prove that 0 < E (W) < if, and only if, , where
We further show that functions (x)=x L(x) which are regularly varying of order 1 at are covered by this result if {2 n : n 0 } and under an additional condition also if =2 n for some n0. This was obtained in a slightly weaker form and analytically by Bingham and Doney. If > 1, then grows at the same order of magnitude as (x) so that and E (Z 1)< are equivalent. However, =1 implies and hence that is a strictly stronger condition than E (Z 1) < . If (x)=x log p x for some p > 0 it can be shown that grows like x log p+1 x, as x. For this special case the result is due to Athreya. As a by-product we also provide a new proof of the Kesten–Stigum result that E Z 1 log Z 1 < and EW > 0 are equivalent.  相似文献   

9.
Letk and be positive integers, andG a 2-connected graph of ordern with minimum degree and independence number. A cycleC ofG is called aD -cycle if every component ofG – V(C) has order smaller than. The graphG isk-cyclable if anyk vertices ofG lie on a common cycle. A previous result of the author is that if k 2, G isk-connected and every connected subgraphH ofG of order has at leastn +k 2 + 1/k + 1 – vertices outsideH adjacent to at least one vertex ofH, thenG contains aD -cycle. Here it is conjectured that k-connected can be replaced by k-cyclable, and this is proved fork = 3. As a consequence it is shown that ifn 4 – 6, or ifG is triangle-free andn 8 – 10, thenG contains aD 3-cycle orG , where denotes a well-known class of nonhamiltonian graphs of connectivity 2. As an analogue of a result of Nash-Williams it follows that ifn 4 – 6 and – 1, thenG is hamiltonian orG . The results are all best possible and compare favorably with recent results on hamiltonicity of graphs which are close to claw-free.  相似文献   

10.
A conjugacy betweenC 1+ -hyperbolic circle covering maps isC 1+ if it has a positive derivative on some point in the -set.  相似文献   

11.
We construct -framed Kripke models of i1 and i1 non of whose worlds satisfies xy(x=2yx=2y+1) and x,yzExp(x, y, z) respectively. This will enable us to show that i1 does not prove ¬¬xy(x=2yx=2y+1) and i1 does not prove ¬¬x, yzExp(x, y, z). Therefore, i1¬¬lop and i1¬¬i1. We also prove that HAl1 and present some remarks about i2. Mathematics Subject Classification (2000):03F30, 03F55, 03H15.  相似文献   

12.
Knessl  Charles  Yang  Yongzhi Peter 《Queueing Systems》2001,39(2-3):213-256
We consider the M/M/ queue with arrival rate , service rate and traffic intensity =/. We analyze the first passage distribution of the time the number of customers N(t) reaches the level c, starting from N(0)=m>c. If m=c+1 we refer to this time period as the congestion period above the level c. We give detailed asymptotic expansions for the distribution of this first passage time for , various ranges of m and c, and several different time scales. Numerical studies back up the asymptotic results.  相似文献   

13.
This paper deals with the analytical properties of -convex functions, which are defined as those functions satisfying the inequalityf(x 1 )+f(x 2 )f(x 1)+f(x 2), forx i [x 1,x 2], |x i x i |=, i=1,2, whenever |x 1x 2|>, for some given positive . This class contains all convex functions and all periodic functions with period . In general, -convex functions do not have ideal properties as convex functions. For instance, there exist -convex functions which are totally discontinuous or not locally bounded. But -convex functions possess so-called conservation properties, meaning good properties which remain true on every bounded interval or even on the entire domain, if only they hold true on an arbitrary closed interval with length . It is shown that boundedness, bounded variation, integrability, continuity, and differentiability almost everywhere are conservation properties of -convex functions on the real line. However, -convex functions have also infection properties, meaning bad properties which propagate to other points, once they appear somewhere (for example, discontinuity). Some equivalent properties of -convexity are given. Ways for generating and representing -convex functions are described.This research was supported by the Deutsche Forschungsgemeinschaft. The first author thanks Prof. Dr. E. Zeidler and Prof. Dr. H. G. Bock for their hospitality and valuable support.  相似文献   

14.
Fix an integerr1. For eachnr, letM nr be the rth largest ofX 1,...,X n, where {X n,n1} is a sequence of i.i.d. random variables. Necessary and sufficient conditions are given for the convergence of n=r n P[|M nr /a n –1|<] for every >0, where {a n} is a real sequence and –1. Moreover, it is shown that if this series converges for somer1 and some >–1, then it converges for everyr1 and every >–1.  相似文献   

15.
Lee  H.W.  Yoon  S.H.  Seo  W.J. 《Queueing Systems》1999,31(1-2):101-124
In this paper, we consider multipleclass queueing systems with Npolicy in which the idle server starts service as soon as the number of customers in the startup class reaches threshold N. We consider the cases of FCFS and nonpreemptive priority. We obtain the Laplace–Stieltjes transform of the waiting times of each class of customers. We also show some results for the general behavior of such systems.  相似文献   

16.
We consider (,,,)structures of parabolic type on hypersurfaces of dual spaces and study the rank of the affinor . We consider almost contact metric structures of parabolic type of the first kind on hypersurfaces of 4dimensional dual metric space. We study the properties of these structures and give examples of normal, integrable, and Sasakian parabolic structures.  相似文献   

17.
Let X be a topological space, ( ) a net of Borel probability measures on X, and (t) a net in ]0,[ converging to 0. Let be a set of continuous functions such that for all x X that can be suitably distinguished by some continuous functions from any closed set not containing contains such a distinguishing function. Assuming that exists for all , we give a sufficient condition in order that ( ) satisfies a large deviation principle with powers (t) and not necessary tight rate function. When X is completely regular (not necessary Hausdorff), this condition is also necessary, and so strictly weaker than exponential tightness; this allows us to strengthen Brycs theorem in various ways. We give the general form of a rate function in terms of . A Prohorov-type theorem with a weaker notion than exponential tightness is obtained, which improves known results.  相似文献   

18.
Let X and Y be metrizable spaces. We show that, for a mapping f : X Y, there exists a quasi-metric X inducing the topology of X such that f regarded as a mapping from (X, max{, –1}) to Y is continuous if and only if f in the original topology of X is a -discrete map of Borel class 1. Further, we prove that, for every -discrete mapping f: X Y of Borel class + 1, there exists a compatible quasi-metric on X such that f : (X, max{, –1}) Y is of Borel class . We also investigate a more general situation when the range of the mapping under consideration is not necessarily metrizable. In passing, we obtain some results related to the behaviour of absolutely Borel sets and absolutely analytic spaces with respect to compatible quasi-metrics.  相似文献   

19.
For each integer n 2, let be the index of composition of n, where . For convenience, we write (1)=(1)=1. We obtain sharp estimates for and , as well as for and . Finally we study the sum of running over shifted primes.Research supported in part by a grant from NSERC.Research supported by the Applied Number Theory Research Group of the Hungarian Academy of Science and by a grant from OTKA.  相似文献   

20.
We prove the completeness and decidability of the Hornlike sequents, specifically, the socalled D2sequents (of the firstorder linear temporal logic) considered in the author's paper [Lith. Math. J., 41(3), 266–281 (2001)]. In this paper, with the help of the infinitary calculus GL, grounded by the author in his earlier papers, for D2sequents we construct a D2Sat calculus of the socalled saturated type consisting of decidable deductive procedures replacing the omegarule for the always operator. In the present paper, in order to prove the completeness and decidability of the calculus D2Sat, we construct the socalled invariant decidable calculus D2IN. We prove the equivalence of the calculi D2IN, D2Sat, and G L ** for the socalled saturated D2sequents. From this equivalence, by reducing an arbitrary D2sequent to a saturated D2sequent, and also from the completeness of the G L ** calculus and decidability of the invariant calculus D2IN, we deduce the completeness and decidability of the calculus D2Sat in the class of D2sequents.  相似文献   

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