# Contents

## Idea

A countable cover is a cover by a countable set of patches.

Accordingly a countable open cover is an open cover with a countable set of patches.

A topological space for which every open cover has a countable subcover is called a Lindelöf space.

Last revised on May 19, 2017 at 05:48:08. See the history of this page for a list of all contributions to it.