How in category.php to output a numbered list of links to pages like:
1 2 3 4 5
when the number of posts in the category exceeds the number of posts to display?
As an alternative to using a plugin like PageNavi(as suggested in another answer), you could also use a wordpress native function
Though the plugin solution seems the easiest to setup
WordPress doesn't output numbered pages by default, but you can use a plugin that does that. WP-PageNavi seems to be the most popular and easiest to setup: http://wordpress.org/extend/plugins/wp-pagenavi/