irreducible

Definition

• A non-empty closed subset C of a topological space (X,τ) is said irreducible if it is not reducible.

Reference

• M.L. Colasante and D. Van der Zypen, Minimal R_1, minimal regular and minimal presober topologies, Revista Notas de Matemática, Vol.5(1),No. 275, 2009, pp.73-84