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991.
We show that a finite completely regular semigroup has a sub-log-exponential free spectrum if and only if it is locally orthodox and has nilpotent subgroups. As a corollary, it follows that the Seif Conjecture holds true for completely regular monoids. In the process, we derive solutions of word problems of free objects in a sequence of varieties of locally orthodox completely regular semigroups from solutions of word problems in relatively free bands.  相似文献   
992.
Let X be a locally compact space with a continuous proper action of a locally compact group G. Assuming that X satisfies a certain kind of duality in equivariant bivariant Kasparov theory, we can enrich the classical construction of Lefschetz numbers for self-maps to an equivariant K-homology class. We compute the Lefschetz invariants for self-maps of finite-dimensional simplicial complexes and smooth manifolds. The resulting invariants are independent of the extra structure used to compute them. Since smooth manifolds can be triangulated, we get two formulas for the same Lefschetz invariant in this case. The resulting identity is closely related to the equivariant Lefschetz Fixed Point Theorem of Lück and Rosenberg.  相似文献   
993.
Our purpose is to view the mathematical contribution of The Ladies' Diary as a whole. We shall range from the state of mathematics in England at the beginning of the 18th century to the transformations of the mathematics that was published in The Diary over 134 years, including the leading role The Ladies' Diary played in the early development of British mathematics periodicals, to finally an account of how progress in mathematics and its journals began to overtake The Diary in Victorian Britain.  相似文献   
994.
We study the mathematical characteristics of the super-universal associated-Legendre polynomials arising from a kind of double ring-shaped potentials and obtain their polar angular wave functions with certain parity. We find that there exists the even or odd parity for the polar angular wave functions when the parameter η is taken to be positive integer, while there exist both even and odd parities when η is taken as positive non-integer real values. The relations among the super-universal associated-Legendre polynomials, the hypergeometric polynomials, and the Jacobi polynomials are also established.  相似文献   
995.
We define a wavelet linear estimator for density derivative in Besov space based on a negatively associated stratified size-biased random sample. We provide two upper bounds of wavelet estimations on L^p (1 ≤ p 〈 ∞) risk.  相似文献   
996.
Given a prime number p, a field F with char(F)=p and a positive integer n, we study the class-preserving modifications of Kato–Milne classes of decomposable differential forms. These modifications demonstrate a natural connection between differential forms and p-regular forms. A p-regular form is defined to be a homogeneous polynomial form of degree p for which there is no nonzero point where all the order p?1 partial derivatives vanish simultaneously. We define a C?p,m field to be a field over which every p-regular form of dimension greater than pm is isotropic. The main results are that for a C?p,m field F, the symbol length of Hp2(F) is bounded from above by pm?1?1 and for any n??(m?1)log2?(p)?+1, Hpn+1(F)=0.  相似文献   
997.
998.
目前,很多地区新冠肺炎疫情已得到缓解,复工、复产已被多地政府部门提上日程.2月10日前后,全国各地返城复工人数增多,2月14日开始,广东、河南等地新增病例数出现了明显反弹,人口跨地区迁徙使疫情防控更加困难.目前全国返工、返校需求还远未得到满足,需要通过数据分析,对"返城复工"的风险进行评估.通过观察数据可以发现人口迁徙与新增确诊病例数有很强的正相关性,因此由"格兰杰因果检验"确定了人口迁徙与新增确诊病例数有显著的因果关系.  相似文献   
999.
In this paper, we provide generalizations of two identities of Guo and Yang [2] for the q-binomial coe?cients. This approach allows us to derive new convolution identities for the complete and elementary symmetric functions. New identities involving q-binomial coe?cients are obtained as very special cases of these results. A new relationship between restricted partitions and restricted partitions into parts of two kinds is derived in this context.  相似文献   
1000.
In a recent paper, the authors gave two new identities for compositions, or ordered partitions, of integers. These identities were based on closely-related integer partition functions which have recently been studied. In the process, we also extensively generalized both of these identities. Since then, we asked whether one could generalize one of these results even further by considering compositions in which certain parts could come from t kinds (rather than just two kinds, which was the crux of the original result). In this paper, we provide such a generalization. A straightforward bijective proof is given and generating functions are provided for each of the types of compositions which arise. We close by briefly mentioning some arithmetic properties satisfied by the functions which count such compositions.  相似文献   
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