Generic theorems in the theory of cardinal invariants of topological spaces

Alejandro Ramírez-Páramo, Jesús F. Tenorio


The main aim of this paper is to present a technical result, which provides an algorithm to prove several cardinal inequalities and relative versions of cardinal inequalities related. Moreover, we use this result and the weak Hausdorff number, H, introduced by Bonanzinga in [Houston J. Math. 39 (3) (2013), 1013–1030], to generalize some upper bounds on the cardinality of topological spaces.


cardinal functions; compact spaces; Lindelöf spaces; weak Hausdorff number of a space

Subject classification

54A25; 54D10.

Full Text:



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