Template:Category see also/Category pair check

Check whether Template:Category see also has been used when Template:Category pair probably should be use.

The test is:
 * 1) Is this page in the Category namespace?
 * 2) Does this page's title end in "nn(st|nd|rd|th))-century something"
 * 3) does the first linked cat's title end in the same "-century something" as the title of the page it is used on?

If the answer to all 3 is yes, then categorise the page in the hidden tracking category Category:Template Category see also used when Template Category pair probably should be