The word one can be used as a pronoun. In this example, the word one stands for the phrase “A coordination”.
A coordination with a conjunction is called syndetic, and one without a conjunction is called asyndetic.
The phrase one another means “each other”.
The two tests are independent of one another.
The pronoun one, when used this way, can be pluralized. In the example below, ones stands for “trials”.
We did not have time to repeat all the trials, so we re-ran only the ones that seemed the most promising.
Note that when one is used as a pronoun, it cannot be substituted by a numeral 1.
[Compare: In the following example, one is first used as a numerical pronoun. In its second use (one‘s), it is an indefinite pronoun.
One way of proving one’s masculinity is to test it against other men.]