Diophantine方程(a-1)x~2+f(a)=4a~n的一点注记

设a是大于1的正整数,f(a)是a的非负整系数多项式,f(1)=2rp+4,其中r是大于1的正整数,p=2~l-1是Mersenne素数.本文讨论了方程(a-1)x~2+f(a)=4a~n的正整数解(x,n)的有限性,并且证明了:当f(a)=91a+9时,该方程仅当a=5,7和25时分别有解(x,n)=(3,3),(11,3)和(3,4).     

Sufficient conditions for asymptotic normality of sums of values of discrete random fields,dependent in strips

Sufficient conditions are given for the asymptotic normality of a sum of values of a field on a square of the integer lattice in R² with the side n for normalization by the quantity (2n+1)^3/2. Moreover, the values of the field are dependent on strips of fixed width. The method of moments is used for proof.Translated from Matematicheskie Zametki, Vol. 23, No. 5, pp. 725–732, May, 1978.     

Monomial Gorenstein ideals

The paper concerns itself with generating sets for monomial Gorenstein ideals in polynomial rings k[x₁,..., x_r], k an arbitrary field. For r=5 it is shown that for a certain class of these ideals, the number of generators is bounded by 13. To establish the sharpness of this bound an algorithm is established, to obtain all numerical symmetric semigroups with a fixed odd integer 2n+1 as last integer unattained. Finally, a short proof of the known fact is given, that for r=4 the number of elements in a generating set is 3 or 5.     

Triangular Cm interpolation by rational functions

Two general local C^m triangular interpolation schemes by rational functions from C^m data are proposed for any nonnegative integer m. The schemes can have either 2m+1 order algebraic precision if the required data are given on vertices and edges, or m+E[m/2]+1 or m+1 order algebraic precision if the data are given only at vertices. The orders of the interpolation error are estimated. Examples that show the correctness and effectiveness of the scheme are presented.     

Triangular Cm interpolation by rational functions

Two general local C^m triangular interpolation schemes by rational functions from C^m data are proposed for any nonnegative integer m. The schemes can have either 2m+1 order algebraic precision if the required data are given on vertices and edges, or m+E[m/2]+1 or m+1 order algebraic precision if the data are given only at vertices. The orders of the interpolation error are estimated. Examples that show the correctness and effectiveness of the scheme are presented. Supported partially by NSFC under Project 1967108 and Croucher Foundation of Hong Kong; Supported also by FRG of Hong Kong Paptist University.     

Linear spaces withn + n + 2lines

It is shown that every non-degenerate linear space withn² + n + 2lines,n ≥ 6, hasv n² + 1 − epoints, whereeis the unique positive real number withn =½e(e + 1). For values ofnfor whicheis an integer, it is shown that the linear spaces withn² + 1 − epoints andn² + n + 2lines are related to symmetric divisible designs.     

代数体函数及其微分多项式

本文证明了v值代表体函数w的微分多项式p(w)是-λ(1<λ相似文献   

关于奇算术图

本文讨论了$n$个$m$长圈有一个公共结点图$C^n_m$, $n$个$m$长圈与$t$长路有一个公共结点图$C^n_m\cdot P_t$, $n$个$m$阶完全图有一个公共结点图$K^n_m$和星形图的同胚图的奇算术性问题.给出了完全图,完全二部图和圈是奇算术的充要条件.     

关于本原商高数的Miyazaki猜想

设a,b,c是适合a=2~(2r)-n~2,b=2~(r+1)n,c=2~(2r)+n~2的正整数,其中r是正整数,n是奇素数.运用初等数论方法讨论了指数Diophantine方程c~x+b~y=a~z.证明了:当2~r=n+1时,方程仅有正整数解(x,y,z)=(1,1,2);否则,方程无解。上述结果部分地证实了有关本原商高数的Miyazaki猜想。     

临界状态下的三项Diophantine方程

本文研究临界状态下三项Diophantine方程解的问题.运用无穷递降法证明了:设m,n,r是大于1的正整数,当1/m+1/n+1/r=1时,方程xm+yn=zn,min(x,y,z)>1,gcd(x,y)=1无正整数解(x,y,z).     

Bipartite Graphs Kn,n+r- A (|A| ≤ 3) Determined by Their Cycle Length Distributions

The cycle length distribution of a graph G of order n is a sequence (c1 (G),..., cn (G)), where ci(G) is the number of cycles of length i in G. In general, the graphs with cycle length distribution (c1(G),...,cn(G)) are not unique. A graph G is determined by its cycle length distribution if the graph with cycle length distribution (c1 (G),..., cn (G)) is unique. Let Kn,n+r be a complete bipartite graph and A(∈)E(Kn,n+r). In this paper, we obtain: Let s > 1 be an integer. (1) If r = 2s, n > s(s - 1) + 2|A|, then Kn,n+r - A (A(∈)E(Kn,n+r),|A| ≤ 3) is determined by its cycle length distribution; (2) If r = 2s + 1,n > s2 + 2|A|, Kn,n+r - A (A(∈)E(Kn,n+r), |A| ≤ 3) is determined by its cycle length distribution.     

由圈长分布确定的二部图~$K_{n,n r}-A\ (|A|\leq 3)$

The cycle length distribution of a graph G of order n is a sequence （c1 （G）,…, cn （G））, where ci （G） is the number of cycles of length i in G. In general, the graphs with cycle length distribution （c1（G） ,…,cn（G）） are not unique. A graph G is determined by its cycle length distribution if the graph with cycle length distribution （c1 （G）,…, cn （G）） is unique. Let Kn,n＋r be a complete bipartite graph and A lohtaib in E（Kn,n＋r）. In this paper, we obtain： Let s 〉 1 be an integer. （1） If r = 2s, n 〉 s（s - 1） ＋ 2｜A｜, then Kn,n＋r - A （A lohtain in E（Kn,n＋r）,｜A｜ ≤ 3） is determined by its cycle length distribution; （2） If r = 2s ＋ 1,n 〉 s^2 ＋ 2｜A｜, Kn,n＋r - A （A lohtain in E（Kn,n＋r）, ｜A｜ ≤3） is determined by its cycle length distribution.     

Theoretical and empirical convergence results for additive congruential random number generators

Additive Congruential Random Number (ACORN) generators represent an approach to generating uniformly distributed pseudo-random numbers that is straightforward to implement efficiently for arbitrarily large order and modulus; if it is implemented using integer arithmetic, it becomes possible to generate identical sequences on any machine.This paper briefly reviews existing results concerning ACORN generators and relevant theory concerning sequences that are well distributed mod 1 in k dimensions. It then demonstrates some new theoretical results for ACORN generators implemented in integer arithmetic with modulus M=2^μ showing that they are a family of generators that converge (in a sense that is defined in the paper) to being well distributed mod 1 in k dimensions, as μ=log₂M tends to infinity. By increasing k, it is possible to increase without limit the number of dimensions in which the resulting sequences approximate to well distributed.The paper concludes by applying the standard TestU01 test suite to ACORN generators for selected values of the modulus (between 2⁶⁰ and 2¹⁵⁰), the order (between 4 and 30) and various odd seed values. On the basis of these and earlier results, it is recommended that an order of at least 9 be used together with an odd seed and modulus equal to 2^30p, for a small integer value of p. While a choice of p=2 should be adequate for most typical applications, increasing p to 3 or 4 gives a sequence that will consistently pass all the tests in the TestU01 test suite, giving additional confidence in more demanding applications.The results demonstrate that the ACORN generators are a reliable source of uniformly distributed pseudo-random numbers, and that in practice (as suggested by the theoretical convergence results) the quality of the ACORN sequences increases with increasing modulus and order.     

LIE ALGEBRA K$(n,\mu _j,m)$ OF CARTAN TYPE OF CHARACTERISTIC p=2

Let $K(n,\mu _j,m),n=2r+1$,denote the Lie algebra of characteristic p=2,which is defined in [4].In the paper the restrictability of $K(n,\mu _j,m)$ is discussed and it is proved that,when $r\equiv 1(mod 2)$ and $r>1,I(ad f)=n+1$ if and only if $0\neq f \in $. Then the invariance of some filtrations of K(n,\mu,m) and the condition of isomorphism of K(n,\mu _i,m) and K(n',\mu _j ^',m') are obtained.Besides,the generators and the derivation algebra of K(n,\mu _i,m) are discussed.The results also hold,when $r\equiv 0 (mod 2)$ and r>0.     

特殊多面体的笵形和同伦群

<正> 多面体的伦型鉴定问题,已经有过许多拓扑工作者的研究.J.H.C.Whitehead找到 A_n~2多面体的伦型和正则上同调环头(n=2)或正则上同调系统类(n>2)间的一一对应.他和 S.Machane 发见“三型”所对应的代数构造,于是引起(?)     

Almost-regular factorization of graphs

For integers a and b, 0 ? a ? a ? b, an [a, b]-graph G satisties a ? deg(x, G) ? b for every vertex x of G, and an [a, b]-factor is a spanning subgraph F such that a ? deg(x, F) ? b for every vertex x of F. An [a, b]-factor is almost-regular if b = a + 1. A graph is [a, b]-factorable if its edges can be decomposed into [a, b]-factors. When both K and t are positive integers and s is a nonnegative integer, we prove that every [(12K + 2)t + 2ks, (12k + 4)t + 2ks]-graph is [2k,2k + 1]-factorable. As its corollary, we prove that every [r.r + 1]-graph with r ? 12k² + 2k is [2k + 1]-factorable, which is a partial extension of the two results, one by Thomassen and the other by Era.     

Functional Gabor frame multipliers

A Gabor frame multiplier is a bounded operator that maps normalized tight Gabor frame generators to normalized tight Gabor frame generators. While characterization of such operators is still unknown, we give a complete characterization for the functional Gabor frame multipliers. We prove that a L^∞ -function h is a functional Gabor frame multiplier (for the time-frequency lattice aℤ × bℤ) if and only if it is unimodular and is a-periodic. Along the same line, we also characterize all the Gabor frame generators g (resp. frame wavelets ψ) for which there is a function ∈ L^∞(ℝ) such that {wg_mn} (resp. ωψ_k,ℝ) is a normalized tight frame.     

Modelling 3-configurations on Surfaces

A 3-configuration is a finite geometry satisfying axioms: (i) each line contains exactly 3 points; (ii) each point is on exactly r lines, where r is a fixed positive integer; and (iii) each pair of distinct points are on at most one common line. Such geometries correspond to K_3⁻ decompositions of their Menger graphs, and hence to bichromatic dual surface (or pseudosurface) imbeddings of these graphs where one color class consists of triangular regions modelling the lines of the geometry. Such imbeddings have been found for all 320 pairs (v, r), where v is the number of points in the geometry, satisfying 2r + 1 ≤ v ≤ 50 and vr ≡ 0 (mod 3). Here we discuss some of the more interesting among these.     

Scattering of small solutions to generalized benjamin-bona-mahony equation in several space dimensions

We show that the supremum norm of solutions with small initial data of the generalized Benjamin-Bona-Mahony equation u_t-△u_t=(b,▽u)+u^p(a,▽u)in x?Rⁿ,n≥2, with integer p≥3 , decays to zero like t^-2/3 if n=2 and like t^-1+6, for any δ0, if n≥3, when t tends to infinity. The proofs of these results are based on an analysis of the linear equation u_t-△=(b,▽u)) and the associated oscillatory integral which may have nonisolated stationary points of the phase function.