关于纯指数丢番图方程a~x+b~y=(m~2+1)~z

设r和m都是正偶数,(a,b,c)=(|V(m,r)|,|U(m,r)|,m~2+1),这里V(m,r)+U(m,r)(-1)~(1/2)=(m+(-1)~(1/2))~r.本文同时使用两个代数数的对数线性型的下界估计和两个有理数方幂之差的p-adic赋值的下界估计的一些结果以及本原素因数的结论证明了:(1)m48400r~2(log r)~2,或(2)m1.4r~2,r≡0(mod 4),2|x,2|y时,方程a~x+b~y=c~z仅有正整数解(x,y,z)=(2,2,r).     

关于整数集分拆的一个猜测的证明

设n为正整数,记rn=m ax{正整数m:可将集合{1,2,…,m}分为n个子集,使得在每一子集中方程xy=z(x>1,y>1)均无解}.高楠和刘红艳(数学的实践与认识,2005,35(5):151—152)给出了rn的一个下界估计rn n9,并猜测对任意给定的正整数k,当n充分大时有rn nk.本文对此猜测给以肯定回答,并证明了如下更强的结论:对任意给定的正整数k 4,当n>3k时有rn n2k+1.     

广义Ramanujan-Nagell方程x~2+D~m=p~n的解的注记

设a为偶数,p为素数,D=3a~2+1,p=4a~2+1。本文指出了乐茂华文献中的错误,并利用两个对数的线性型上界估计的P-adic形式以及广义Fermat方程的解的一些新结论,证明了方程x~2+D~m=p~n仅有两组正整数解(x,m,n)=(0,1,1),(8a~3+ 3a,1,3)．     

关于Diophantine方程a~x+b~y=c~z的Terai猜想

设m是正偶数.证明了(A)若b是奇素数,且a=m|m~6-21m~4+35m~2-7|,b=|7m~6-35m~4+21m~2-1|,c=m~2+1,则Diophantine方程G:a~x+b~y=c~z仅有正整数解(x,y,z)=(2,2,7);(B)若m2863,且a=m|m~8-36m~6+126m~4-84m~2+9|,b=|9m~8-84m~6+126m~4-36m~2+1|,c=m~2+1,则Diophantine方程G仅有正整数解(x,y,z)=(2,2,9);(C)若a,b,c适合a=m|∑_(i=0)~((r-1)/2)(-1)~i(_(2i)~r)m~(r-2i-1)|,b=|∑_(i=0)~((r-1)/2)(-1)~i(_(2i+1)~r)m~(r-2i-1)|,c=m~2+1,r≡1(mod4),2|x,2|y,且b为奇素数或m145r(log r),则方程G仅有解(x,y,z)=(2,2,r).     

指数丢番图方程a~x+b~y=c~z

设a=|m(m~4-10m~2+5)|,b=5m~4-10m~2+1,c=m~2+1,其中m是正偶数。利用Bilu,Hanrot和Voutier关于本原素除子的深刻结果,证明了指数丢番图方程a~x+b~y=c~z仅有正整数解(x,y,z)=(2,2,5)。     

关于方程ax+by=cz的Terai-Jesmanowicz猜想

设m是正整数,证明了:(A)如果b是奇素数,且a=m3-3m,b=3m2-1,c=m2+1,那么丢番图方程ax+by=cz(1)仅有正整数解(x,y,z)=(2,2,3);(B)如果b是奇素数,且a=m|m4-10m2+5|,b=5m4-10m2+1,c=m2+1,那么丢番图方程(1)仅有正整数解(x,y,z)=(2,2,5).     

关于方程ax+by=cz的Terai-Jesmanowicz猜想

设m是正整数,证明了(A)如果b是奇素数,且a=m3-3m,b=3m2-1,c=m2+1,那么丢番图方程ax+by=cz(1)仅有正整数解(x,y,z)=(2,2,3);(B)如果b是奇素数,且a=m|m4-10m2+5|,b=5m4-10m2+1,c=m2+1,那么丢番图方程(1)仅有正整数解(x,y,z)=(2,2,5).     

连分数对数的线形型下界

给出了一类连分数的对致的线形型的下界估计:设{an是给定的正整致列,a与β是y=f(s)=alx+/1 a2x+/1…anx+/1 …在两个不同的正整数点的值,k和l是不全为零的整数,则存在常数c4,c6,使得|A|=|klog a+flog βI>c6exp(-c4Alog H),其中A=max{λ(μ(1ogH+1)+1),λ(μlogH+1)+2)}.     

紧流形上椭圆微分算子预解式的一致L~p-L~q估计

假设n和m是两个正整数,P(x,D)是定义在维数为n的紧致无边流形M上的一般m阶椭圆自伴微分算子.在一定条件下,本文主要证明微分算子P(x,D)的预解式的一致Lp-Lq估计,其中nm 2,(p,q)在Sobolev线上并满足1p-1q=m n,p 2(n+1)n+3,q 2(n+1)n-1.本文的一个核心引理是建立曲面Σx={ξ∈T*x(M):p(x,ξ)=1}上测度的Fourier变换衰减估计的具体表达式,并利用它来得到局部算子的一致Lp-Lq估计.     

广义Ramanujan-Nagell方程x~2+D~m=p~n的解数

设a是正整数,D=3a2+1,P=4a2+1,其中p是素数.本文证明了:如果a不是4的倍数,则除了当(D,p)=(4,5)时方程x2+Dm=pn恰有3组正整数解(x,m,n)=(1,1,1),(3,2,2),(11,1,3)以外,该方程恰有2组正整数解(x,m,n)=(a,1,1)和(8a3+3a,1,3).     

Estimates of stability of characterization of additive types of distributions

An estimate of stability of characterization of distribution types is obtained for the case of additive types. Under some conditions, the estimate has the order ε^1/3L(ε), where L(ε) is a slowly varying function. Proceedings of the Seminar on Stability Problems for Stochastic Models, Moscow, Russia, 1996, Part I.     

Study of the blow-up of solutions of systems of equations of hydrodynamic type

Mathematical Notes - We study the initial boundary-value problem for three-dimensional systems of equations of pseudoparabolic type. The system is similar to the Oskolkov system, but differs from...     

Characterization of types of asymptotic discernibility of families of hypotheses

We give a characterization of the types of asymptotic discernibility of families of hypotheses in the case of hypothetical measures that are not, in general, mutually absolutely continuous. The case when the logarithm of the likelihood ratio admits an asymptotic expansion of the type of an expansion with local asymptotic normality is examined in detail. Examples are studied.Translated fromTeoriya Sluchainykh Protsessov, Vol. 15, pp. 64–71, 1987.     

一类完全正则半群簇子簇格的性质

本文研究了完全正则半群簇的子簇格［Ｖ＋∩ＰＶ，Ｖ＋∩ＰＶ］的某些格运算性质，我们证明了簇Ｖ＋∩ＰＶ可分解为Ｖ与Ｖ＋∩ＰＶ的并；对任意完全正则半群簇Ｗ，有Ｗ∩（Ｖ∨Ｖ＋∩ＰＶ）＝（Ｗ∩Ｖ）∨（Ｗ∩Ｖ＋∩ＰＶ）．特别地，我们得到了等式Ｖ＋∩ＰＶ＝Ｖ成立的若干条件．     

Distribution of types of symmetry of tensors of high degree

The asymptotic distribution of tensors of degree N in symmetry types is studied in this paper.Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova AN SSSR, Vol. 155, pp. 181–186, 1986.     

Birational aspects of the geometry of Varieties of Sums of Powers

Varieties of Sums of Powers describe the additive decompositions of a homogeneous polynomial into powers of linear forms. The study of these varieties dates back to Sylvester and Hilbert, but only few of them, for special degrees and number of variables, are concretely identified. In this paper we aim to understand a general birational behavior of VSP. To do this we birationally embed these varieties into Grassmannians and prove the rational connectedness of many VSP in arbitrary degrees and number of variables.     

Estimate of growth of Lebesgue functions of linear methods of summation

Sufficient conditions are obtained in terms of matrix elements for the boundedness of Lebesgue functions of linear methods of summation of expansions in orthogonal systems of polynomial type.Translated from Matematicheskie Zametki, Vol. 6, No. 3, pp. 277–286, September, 1969.