摘要:

Let R be a ring, Z its center, U a nonzero left ideal, and D:R → R a derivation. We show that if R is semiprime with suitably-restricted additive torsion, then R must contain nonzero central ideals if one of the following holds: (i) [x, [x, D(x)]] ∈ Z for all x ∈ U; (ii) for a fixed positive integer n, [xn, D(x)] ∈ Z for all x ∈ U

ISSN:0092-7872    

DOI:10.1080/00927879508825427

出版商:Marcel Dekker, Inc.    

年代:1995

数据来源: Taylor

摘要:

We give significant improvements to the Graham, Knuth & Motzkin result: ifRis any binary relation,R+c+c+=R+c+c(whereP+denotes the transitive closure of the binary relationP, andPcits Boolean complement)

ISSN:0092-7872    

DOI:10.1080/00927879508825428

出版商:Marcel Dekker, Inc.    

年代:1995

数据来源: Taylor

ISSN:0092-7872    

DOI:10.1080/00927879508825429

出版商:Marcel Dekker, Inc.    

年代:1995

数据来源: Taylor

ISSN:0092-7872    

DOI:10.1080/00927879508825430

出版商:Marcel Dekker, Inc.    

年代:1995

数据来源: Taylor

ISSN:0092-7872    

DOI:10.1080/00927879508825431

出版商:Marcel Dekker, Inc.    

年代:1995

数据来源: Taylor

ISSN:0092-7872    

DOI:10.1080/00927879508825432

出版商:Marcel Dekker, Inc.    

年代:1995

数据来源: Taylor

摘要:

The extended genus of a nilpotent groupNis the set of isomorphism classes of nilpotent groupsM,not necessarily finitely generated, such that thep-localizationsMp,Npare isomorphic for all primesp. In this article, for any torsion-free finitely generated nilpotent groupNof nilpotency class 2, the extended genus ofNis analyzed by assigning to each of its members a sequence of triads of matrices with rational entries, generalizing the sequential representation which has been exploited elsewhere in the case whenNis abelian. This approach allows, among other things, to obtain examples of groups in the ordinary (Mislin) genus ofN

ISSN:0092-7872    

DOI:10.1080/00927879508825433

出版商:Marcel Dekker, Inc.    

年代:1995

数据来源: Taylor

ISSN:0092-7872    

DOI:10.1080/00927879508825434

出版商:Marcel Dekker, Inc.    

年代:1995

数据来源: Taylor

摘要:

For all groups G and N-seriesNof G a functorial description is given for the first three quotients of the filtration of the integral group ring which is induced byNAs a key toolN,-polynomial maps on G are introduced and studied; an inductive characterization of such maps is given and used to identify an important class of nonlinear functions asN-polynomial maps.

ISSN:0092-7872    

DOI:10.1080/00927879508825435

出版商:Marcel Dekker, Inc.    

年代:1995

数据来源: Taylor

ISSN:0092-7872    

DOI:10.1080/00927879508825436

出版商:Marcel Dekker, Inc.    

年代:1995

数据来源: Taylor