Only the indefinitely stable ones are a clearly countable set.

Every countable partially ordered set can be embedded in the Turing degrees.

Another example is the set of hereditarily countable sets.

The distinction is made between a countable set and an uncountable set.

In other words, that there be some countable set of coordinates whose values determine the whole random function f.

For instance, one might expect that adding a countable set would have no effect on the dimension of a set.

If you can count the things in a set, it is called a countable set.

Sometimes when people say 'countable set' they mean countable and infinite.

Any compact subset of R must be a countable set.

So all the c are distinct, and X contains a countable set.