Given a non-empty set X, a collection of subsets of X is called an ideal:
1) If and implies (Heredity)
2) If and implies (Additivity)
If then is called a proper ideal.
An ideal is called a ideal if the following holds: If {An: n = 1, 2, …...} is a
countable sub-collection of , then {An : n = 1, 2, ….}
The notation denotes a non-empty set X, a topology on X and an
ideal on X. Given point denotes the neighborhood system of x, i.e., . The symbol denotes collection of all subsets of X.
Given space and a subset A of X, we define for every .
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