Cofinite Filter of $B$ centered at $A$ (Definition II.4.3)
QUESTION
Cofinite Filter of $B$ centered at $A$ (Definition II.4.3)
Click to reveal answer ANSWER
For $A \subset B \subset X$, the filter:
$$(B, A)_0 := \{F \subset X : A \subset F, \operatorname{card}(B \setminus F) < \infty\}$$
It decomposes as $(B, A)_0 = (B \setminus A)_0 \wedge \{A\}^\uparrow$.
Click to see question - ソースノート: chapter2.md
- カードID: cofinite-filter-of-b-centered-at-a
- 状態: active