The pages you are talking about are specific to PHPMyAdmin, to help user have a more understandable interface, by only showing a specific number of rows. So it doesn't really matter which page they are, and it would change from a project to another.
What you need to do is look for the path you want with a SQL query (or with a search if you are using phpmyadmin or a similar tool).
You could use this request :
SELECT * FROM core_config_data WHERE path LIKE "%admin/url/%";
This will select all the rows where the path contains "admin/url/", then you should be able to modify them.
If you are using phpmyadmin, you can go to the sql section and execute this command, or go to the search section, and search for the path you want to find.