Alas, Ofelia T.; Wilson, Richard G.(Universitat Politècnica de València, 2007-10-01)
[EN] We introduce a class of spaces in which every discretesubset has a complete accumulation point. Properties of this classare obtained and consistent examples are given to show that this classdiffers from the ...
Alas, Ofelia T.; Madriz-Mendoza, Maira; Wilson, Richard G.(Universitat Politècnica de València, 2012-04-01)
[EN] We prove some cardinal inequalities valid in the classes of Whyburn and hereditarily weakly Whyburn spaces and we construct examples of non-Whyburn and non-weakly Whyburn spaces to illustrate that some previously known ...
Alas, Ofelia T.; Tamariz-Mascarúa, Ángel(Universitat Politècnica de València, 2008-04-01)
[EN] The Cech number of a space Z, C(Z), is the pseudocharacter of Z in βZ. In this article we obtain, in ZFC and assuming SCH, some upper and lower bounds of the Cech number of spaces Cp(X) of realvalued continuous ...
Alas, Ofelia T.; Wilson, Richard G.(Universitat Politècnica de València, 2011-04-01)
[EN] We study the subposet E3(X) of the lattice L1(X) of all T1-topologies on a set X, being the collections of all T3 topologies on X, with a view to deciding which elements of this partially ordered set have and which ...
Alas, Ofelia T.; Wilson, Richard G.(Universitat Politècnica de València, 2004-10-01)
[EN] We give a new characterization of those topologies which have an immediate successor or cover in the lattice of T1-topologies on a set and show that certain classes of compact and countably compact topologies do not ...