λ-T_{1/2}

Definition

• A topological space (X, τ) is called λ-T_{1/2} if every singleton is λ-open or λ-closed.

Reference

• Caldas Miguel, Jafari Saeid, On some low separation axioms via λ-open and λ-closure operator., Rend. Circ. Mat. Palermo (2) 54 (2005), no. 2, 195–208.