ABSTRACT. An zdeal on a set X is a nonempty collection of subsets of X closed under the operatio,s of (heredity) and finite unions (additivity). Given a topological space (X,v) an ideal on X and A C_X, /'(A) defined as U{UEv:U-AE3}. A topology, denoted r*, finer than is generated by the basis {U-I:U(r, IE3}, ,,d a topology, denoted <(r)>, coarser than r is generated by the basis (v) {(U):UEv}.
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