ON STRONGLY AND SEPARABLY ?1-p?+n-PROJECTIVE ABELIAN p-GROUPS

ON STRONGLY AND SEPARABLY ?1-p?+n-PROJECTIVE ABELIAN p-GROUPS

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 ?1-p?+n-projective andseparably ?1-p?+n-projective abelian p-groups which are also properlycontained in all ?1-p?+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.

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  • [1] K. Benabdallah, J. Irwin and M. Rafiq, A core class of abelian p-groups, Sympos. Math. 13 (1974), 195-206.
  • [2] P. Danchev, Countable extensions of torsion abelian groups, Arch. Math. (Brno) 41 (3) (2005), 265-272.
  • [3] P. Danchev, Primary abelian n-?-groups revisited, Math. Pannonica 22 (1) (2011), 85-93.
  • [4] P. Danchev, On weakly ?1-p ?+n-projective abelian p-groups, J. Indian Math. Soc. 80 (1-4) (2013), 33-46.
  • [5] P. Danchev, On ?1-weakly p ?-projective abelian p-groups, Bull. Malays. Math. Sci. Soc. 37 (2014).
  • [6] P. Danchev and P. Keef, Generalized Wallace theorems, Math. Scand. 104 (1) (2009), 33-50.
  • [7] P. Danchev and P. Keef, An application of set theory to ? + n-totally p ?+n-projective primary abelian groups, Mediterr. J. Math. 8 (4) (2011), 525-542
  • [8] P. Danchev and P. Keef, On n-simply presented primary abelian groups, Houston J. Math. 38 (4) (2012), 1027-1050.
  • [9] L. Fuchs, Infinite Abelian Groups, Volumes I and II, Academic Press, New York and London 1970 and 1973.
  • [10] L. Fuchs and J. Irwin, On elongations of totally projective p-groups by p ?+n-projective
  • p-groups, Czechoslovak Math. J. 32 (4) (1982), 511-515.
  • [11] P. Keef, Elongations of totally projective groups and p ?+n-projective abelian groups, Commun. Algebra 18 (12) (1990), 4377-4385.
  • [12] P. Keef, On ?1-p ?+n-projective primary abelian groups, J. Alg. Numb. Th. Acad. 1 (1) (2010), 41-75.
  • [13] C. Megibben, On high subgroups, Pac. J. Math. 14 (4) (1964), 1353-1358.
  • [14] R. Nunke, Purity and subfunctors of the identity, Topics in Abelian Groups, Scott, Foresman and Co., 1962, 121-171.