p-series

<正>Last time we learn what the integral test is.Now,well learn how to use the integral test.Example 1:Determine whether the series below converges or diverges.     

Homology groups of semicubical sets

We study the homology groups of semicubical sets with coefficients in the homological systems of abelian groups. The main theorem states that the groups under consideration are isomorphic to the homology groups of the category of singular cubes. This yields an isomorphism criterion for the homology groups of semicubical sets, the spectral sequence of a locally directed covering, and the spectral sequence of a morphism of semicubical sets.     

Homology groups,nearfields and reguli

In this article, we characterize translation planes of orderq ² and kernel KGF(q) which admit an affine homology group of orderq–1 and a regulus which contains the axis or coaxis in its spread.     

Homology stability for linear groups

Summary LetR be a commutative finite dimensional noetherian ring or, more generally, an associative ring which satisfies one of Bass' stable range conditions. We describe a modified version of H. Maazen's work [18], yielding stability for the homology of linear groups overR. Applying W.G. Dwyer's arguments (cf. [9]) we also get stability for homology with twisted coefficients. For example,H ₂(GL _n (R), R ⁿ ) takes on a stable value whenn becomes large.     

Homology of gauge groups associated with special unitary groups

We study the homology of gauge groups associated with principal SU(n) bundles over the four-sphere. After computing the mod p homology of based gauge groups of SU(n) by combined use of the Serre spectral sequence and the Eilenberg-Moore spectral sequence, we compute the modp homology of gauge groups of SU(n) using the Serre spectral sequence for the evaluation fibration.     

Homology and cohomology groups of the group homomorphism

As is known, the homology and cohomology Massa-Takasu groups for pairs of groups (G, H) are defined by the embedding f: H → G, H < G [2]. In our case, these definitions are extended to an arbitrary group homomorphism φ: Π → G. In particular, we define homology and cohomology groups of the nth order for the homomorphism φ, and if Π = H, we obtain the known theory [2]. __________ Translated from Sovremennaya Matematika i Ee Prilozheniya (Contemporary Mathematics and Its Applications), Vol. 43, Topology and Its Applications, 2006.     

关于发散的p-级数的一个发散速度估计

设p∈(0,1),本文研究p-级数∑∞n=1n~(-p)的发散速度估计.通过构造适当的区间套,得到了limn→∞A_(n,p):=C_p∈(p,2~(1-p)-1+p),0C_p-A_(n,p)(1-p)n~(-p),这里,A_(n,p)=n~(1-p)-(1-p)∑k=nk=1k~(-p).进一步,应用数值积分的梯形公式,得到了lim_(n→∞)n~p C(_p-A_(n,p))=(1-p)/2以及C_p-A_(n,p)的二次估计.所得结果改进了文(马书燮,关于发散p-级数的一个不等式[J].大学数学,2013,29(2):147-150.)中的结果.     

p级数的求和

通过积分转移、余项逼近的方法,建立起一系列p级数的求和公式,并给出了便于操作的误差估计方法.一改把级数余项当作误差来估计的传统做法,而是将余项作为和的重要组成部分进行分析,使得每增加一项计算量,精度能提升二个以上指数级,从而有效地解决了p级数的求和问题.     

Homology of free Lie powers and torsion in groups

LetG be a group that is given by a free presentationG=F/R, and let_γ4 R denote the fourth term of the lower central series of R. We show that ifG has no elements of order 2, then the torsion subgroup of the free central extensionF/[_γ4 R,F] can be identified with the homology groupR _γ6(G, ℤ/2ℤ). This is a consequence of our main result which refers to the homology ofG with coefficients in Lie powers of relation modules.     

Homology decompositions for p-compact groups

We construct a homotopy theoretic setup for homology decompositions of classifying spaces of p-compact groups. This setup is then used to obtain a subgroup decomposition for p-compact groups which generalizes the subgroup decomposition with respect to p-stubborn subgroups for a compact Lie group constructed by Jackowski, McClure and Oliver.     

Homology decompositions for classifying spaces of compact Lie groups

Let be a prime number and be a compact Lie group. A homology decomposition for the classifying space is a way of building up to mod homology as a homotopy colimit of classifying spaces of subgroups of . In this paper we develop techniques for constructing such homology decompositions. Jackowski, McClure and Oliver (Homotopy classification of self-maps of BG via -actions, Ann. of Math. 135 (1992), 183-270) construct a homology decomposition of by classifying spaces of -stubborn subgroups of . Their decomposition is based on the existence of a finite-dimensional mod acyclic --complex with restricted set of orbit types. We apply our techniques to give a parallel proof of the -stubborn decomposition of which does not use this geometric construction.

     

Homology stability for orthogonal groups over algebraically closed fields

We give the best ranges of stability, for homology of orthogonal groups and special orthogonal groups, over an algebraically closed field, of characteristic different from 2. This answers affirmatively a conjecture asserted in a previous paper. We find distinct ranges of stability for orthogonal and special orthogonal groups, and Milnor K-theory appears as an obstruction to stability for special orthogonal groups. The main results are formulated, more generally, for infinite Pythagorean fields.