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991.
For A ■ Z m and n ∈ Z m ,let σ A (n) be the number of solutions of equation n = x + y,x,y ∈ A.Given a positive integer m,let R m be the least positive integer r such that there exists a set A ■ Z m with A + A = Z m and σ A (n) ≤ r.Recently,Chen Yonggao proved that all R m ≤ 288.In this paper,we obtain new upper bounds of some special type R kp 2 . 相似文献
992.
Let R be a domain and let Rwg be the w-global transform of R. In this note it is shown that if R is a Mori domain, then the t-dimension formula t-dim(Rwg) = t-dim(R) - 1 holds. 相似文献
993.
Let X be a separable infinite dimensional Banach space and B(X) denote its operator algebra,the algebra of all bounded linear operators T : X → X.Define a left multiplication mapping LT : B(X) → B(X) by LT (V ) = T V,V ∈ B(X).We investigate the connections between hypercyclic and chaotic behaviors of the left multiplication mapping LT on B(X) and that of operator T on X.We obtain that LT is SOT-hypercyclic if and only if T satisfies the Hypercyclicity Criterion.If we define chaos on B(X) as SOT-hypercyclicity plus SOT-dense subset of periodic points,we also get that LT is chaotic if and only if T is chaotic in the sense of Devaney. 相似文献
994.
By introducing the resolvent operator associated with a maximal monotone mapping, the author obtains a strong convergence theorem of a generalized iterative algorithm for a class of quasi-variational inclusion problems, which extends and unifies some recent results. 相似文献
995.
996.
A monomial basis and a filtration of subalgebras for the universal enveloping algebra U(gl) of a complex simple Lie algebra gl of type Bl and Cl are given, and the decomposition of the Weyl module V (λ) as a U(gl)-module into a direct sum of Weyl modules V (μ)’s as U(gl-1)modules is described. In particular, a new multiplicity formula for the Weyl module V (λ) is obtained in this note. 相似文献
997.
半模糊凸模糊映射 总被引:1,自引:1,他引:0
In this paper, a new class of fuzzy mappings called semistrictly convex fuzzy mappings is introduced and we present some properties of this kind of fuzzy mappings. In particular, we prove that a local minimum of a semistrictly convex fuzzy mapping is also a global minimum. We also discuss the relations among convexity, strict convexity and semistrict convexity of fuzzy mapping, and give several sufficient conditions for convexity and semistrict convexity. 相似文献
998.
It is well known that finding the crossing number of a graph on nonplanar surfaces is very difficult.In this paper we study the crossing number of the circular graph C(10,4) on the projective plane and determine the nonorientable crossing number sequence of C(10,4).On the basis of the result,we show that the nonorientable crossing number sequence of C(10,4) is not convex. 相似文献
999.
By using the Leray-Schauder fixed point theorem,differential inequality techniques and constructing suitable Lyapunov functional,several sufficient conditions are obtained for the existence and global exponential stability of periodic solutions for general shunting inhibitory cellular neural networks with delays.Some new results are obtained and some previously known results are improved.An example is employed to illustrate our feasible results. 相似文献
1000.
This paper discusses a class of the bidirectional associative memories(BAM) type neural networks with impulse.By using the Banach fixed point theory and some analysis technology,we obtain the existence of almost periodic solution and stability under some sufficient conditions. 相似文献