Properties of Some Kind of Number Theoretical Function（Ⅱ）

For any given positive integer n ≥ 1, the Euler function φ（n） is defined to be the number of positive integers not exceeding n, which is relatively prime to n. o：（n） is defined to be the number of different prime divisors of n. In order to know the solvability of the function of φ（φ（φ（n））） = 2^ω（n）, properties of the number theoretical function φ（φ（n）） is studied in the paper.     

一类奇完全数的一些结论(英文)

Define the total number of distinct prime factors of an odd perfect number n asω(n). We prove that if n is an odd perfect number which is relatively prime to 3 and 5 and7, then ω(n) ≥ 107. And using this result, we give a conclusion that the third largest prime factor of such an odd perfect number exceeds 1283.     

Some Results of a Certain Odd Perfect Numb er

Define the total number of distinct prime factors of an odd perfect number n asω（n）. We prove that if n is an odd perfect number which is relatively prime to 3 and 5 and 7, thenω（n）≥107. And using this result, we give a conclusion that the third largest prime factor of such an odd perfect number exceeds 1283.     

Congruent elliptic curves with non-trivial Shafarevich-Tate groups: Distribution part

Given a large positive number x and a positive integer k, we denote by Qk(x) the set of congruent elliptic curves E(n): y2= z3- n2 z with positive square-free integers n x congruent to one modulo eight,having k prime factors and each prime factor congruent to one modulo four. We obtain the asymptotic formula for the number of congruent elliptic curves E(n)∈ Qk(x) with Mordell-Weil ranks zero and 2-primary part of Shafarevich-Tate groups isomorphic to(Z/2Z)2. We also get a lower bound for the number of E(n)∈ Qk(x)with Mordell-Weil ranks zero and 2-primary part of Shafarevich-Tate groups isomorphic to(Z/2Z)4. The key ingredient of the proof of these results is an independence property of residue symbols. This property roughly says that the number of positive square-free integers n x with k prime factors and residue symbols(quadratic and quartic) among its prime factors being given compatible values does not depend on the actual values.     

Sums of primes and quadratic linear recurrence sequences

Let u be a sequence of positive integers which grows essentially as a geometric progression. We give a criterion on u in terms of its distribution modulo d, d = 1, 2,..., under which the set of positive integers expressible by the sum of a prime number and an element of u has a positive lower density. This criterion is then checked for some second order linear recurrence sequences. It follows, for instance, that the set of positive integers of the form p ＋ [（2 ＋ √3）n], where p is a prime number and n is a positive integer, has a positive lower density. This generalizes a recent result of Enoch Lee. In passing, we show that the periods of linear recurrence sequences of order m modulo a prime number p cannot be ＂too small＂ for most prime numbers p.     

A sharp estimate of positive integral points in 6-dimensional polyhedra and a sharp estimate of smooth numbers

Inspired by Durfee Conjecture in singularity theory, Yau formulated the Yau number theoretic conjecture(see Conjecture 1.3) which gives a sharp polynomial upper bound of the number of positive integral points in an n-dimensional(n≥3) polyhedron. It is well known that getting the estimate of integral points in the polyhedron is equivalent to getting the estimate of the de Bruijn function ψ(x, y), which is important and has a number of applications to analytic number theory and cryptography. We prove the Yau number theoretic conjecture for n = 6. As an application, we give a sharper estimate of function ψ(x, y) for 5≤y 17, compared with the result obtained by Ennola.     

Finitely Generated Torsion-free Nilp otent Groups Admitting an Automorphism of Prime Order

Let G be a finitely generated torsion-free nilpotent group and α an automorphism of prime order p of G. If the map φ : G-→ G defined by gφ= [g, α]is surjective, then the nilpotent class of G is at most h(p), where h(p) is a function depending only on p. In particular, if α3= 1, then the nilpotent class of G is at most2.     

Molecular Characterization of Anisotropic Musielak–Orlicz Hardy Spaces and Their Applications

Let A be an expansive dilation on R~n and φ:R~n× [0,∞)→[0,∞) an anisotropic Musielak–Orlicz function.Let H_A~φ(R~n) be the anisotropic Hardy space of Musielak–Orlicz type defined via the grand maximal function.In this article,the authors establish its molecular characterization via the atomic characterization of H_A~φ(R~n).The molecules introduced in this article have the vanishing moments up to order s and the range of s in the isotropic case(namely,A:=2I_(n×n)) coincides with the range of well-known classical molecules and,moreover,even for the isotropic Hardy space H~p(R~n)with p∈(0,1](in this case,A:=2I_(n×n),φ(x,t) :=t~p for all x∈R~n and t∈[0,∞)),this molecular characterization is also new.As an application,the authors obtain the boundedness of anisotropic Calderón–Zygmund operators from H_A~φ(R~n) to L~φ(R~n) or from H_A~φ(R~n) to itself.     

A Criterion for Elliptic Curves with Second Lowest 2-Power in L（1）（Ⅱ）

Let D = p1p2 …pm, where p1,p2, ……,pm are distinct rational primes with p1 ≡p2 ≡3（mod 8）, pi =1（mod 8）（3 ≤ i ≤ m）, and m is any positive integer. In this paper, we give a simple combinatorial criterion for the value of the complex L-function of the congruent elliptic curve ED2 ： y^2 = x^3- D^2x at s = 1, divided by the period ω defined below, to be exactly divisible by 2^2m-2, the second lowest 2-power with respect to the number of the Gaussian prime factors of D. As a corollary, we obtain a new series of non-congruent numbers whose prime factors can be arbitrarily many. Our result is in accord with the predictions of the conjecture of Birch and Swinnerton-Dyer.     

Primes in arithmetic progressions with friable indices

We consider the numberπ(x,y;q,a)of primes p≤such that p≡a(mod q)and(p-a)/q is free of prime factors greater than y.Assuming a suitable form of Elliott-Halberstam conjecture,it is proved thatπ(x,y:q,a)is asymptotic to p(log(x/q)/log y)π(x)/φ(q)on average,subject to certain ranges of y and q,where p is the Dickman function.Moreover,unconditional upper bounds are also obtained via sieve methods.As a typical application,we may control more effectively the number of shifted primes with large prime factors.     

On the determination of the number of periodic (or closed) solutions of a scalar differential equation with convexity

It is well known that a scalar differential equation , where f(t,x) is continuous, T-periodic in t and weakly convex or concave in x has no, one or two T-periodic solutions or a connected band of T-periodic solutions. The last possibility can be excluded if f(t,x) is strictly convex or concave for some t in the period interval. In this paper we investigate how the actual number of T-periodic solutions for a given equation of this type in principle can be determined, if f(t,x) is also assumed to have a continuous derivative . It turns out that there are three cases. In each of these cases we indicate the monotonicity properties and the domain of values for the function P(ξ)=S(ξ)−ξ, where S(ξ) is the Poincaré successor function. From these informations the actual number of periodic solutions can be determined, since a zero of P(ξ) represents a periodic solution.     

AF—代数的闭的Jordan理想

讨论AF-代数的闭的Jordan理想。我们证明了AF-代灵敏的一个闭的子集是其一Jordan理想的充分必要条件是它是一个结合理想。     

一类拟线性常微分方程的多解

说明一类拟线性特征值问题有两个正解;一个大解,一个小解。同时本也证明小解是一个山路解当参数大时发展成为尖解。     

Solutions of the generalized Lennard-Jones system

In this paper, we study solution structures of the following generalized Lennard-Jones system in R~n,x=(-α/|x|~(α+2)+β/|x|~(β+2))x,with 0 α β. Considering periodic solutions with zero angular momentum, we prove that the corresponding problem degenerates to 1-dimensional and possesses infinitely many periodic solutions which must be oscillating line solutions or constant solutions. Considering solutions with non-zero angular momentum, we compute Morse indices of the circular solutions first, and then apply the mountain pass theorem to show the existence of non-circular solutions with non-zero topological degrees. We further prove that besides circular solutions the system possesses in fact countably many periodic solutions with arbitrarily large topological degree, infinitely many quasi-periodic solutions, and infinitely many asymptotic solutions.     

On the existence of bounded noncontinuable solutions

This paper presents necessary and sufficient conditions for an n ‐th order differential equation to have a non‐continuable solution with finite limits of its derivatives up to the order l at the right‐hand end point of the interval of its definition, l ≤ n – 2 (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

On a class of nonlinear elliptic equations with fast increasing weight and critical growth

We are concerned with the existence of rapidly decaying solutions for the equation

     

Weakly-efficient solutions of limiting multicriteria optimization problems

This paper concerns the connection among different sets of multicriteria optimization problem solutions. For the family of bicriteria optimization problems, the limiting properties of the sets of weakly-efficient solutions are determined.     

一类非线性发展方程的对称分析及级数解

基于李对称理论分析了广义Burgers方程的推广方程,获得其有限维李对称.进一步,研究向量场的伴随表示构造优化系统.最终基于对称约化,获得了方程的约化系统及包含级数解在内的群不变解.