ON STRONGLY AND SEPARABLY ω1-pω+n-PROJECTIVE ABELIAN p-GROUPS

Year 2014, Volume: 43 Issue: 1, 51 - 64, 01.01.2014

Peter Danchev

Abstract

Let n ≥ 0 be an arbitrary integer. We prove some results for stronglyn-simply presented abelian p-groups with C-decomposable property, extending classical achievements due to Keef in Commun. Algebra (1990).As applications we define the classes of strongly ω-p ω+n -projective andseparably ω-p ω+n -projective abelian p-groups which are also properlycontained in all ω-p ω+n -projectives, recently defined by Keef in J. Alg.Numb. Th. Acad. (2010). Moreover, some principal descriptions concerning these new objects are obtained as well.

Keywords

C-decomposable groups, pω+n-projective groups, strongly n-simply presented groups, ω-p ω+n-projective groups, strongly ω-p ω+n-projective groups, boundedsubgroups, countable subgroups, nice subgroups, Ulm subgroups, Ulm factors.

ON STRONGLY AND SEPARABLY ω1-pω+n-PROJECTIVE ABELIAN p-GROUPS

Abstract

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Keywords

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