Cofinite Filter

If S is an infinite set, then the collection F_S={A subset= S:S-A is finite} is a filter called the cofinite (or Fréchet) filter on S.

See also

Filter, Ultrafilter

This entry contributed by Viktor Bengtsson

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Cite this as:

Bengtsson, Viktor. "Cofinite Filter." From MathWorld--A Wolfram Web Resource, created by Eric W. Weisstein.

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