Updated February 22, 2007
The default main index page of a Movable Type weblog displays the last 10 entries made. You can change this number by entering a different number in the weblog's settings. Settings > General > Default Weblog Display Settings > Entries to Display
You can also change the default settings so that they display the last X number of days worth of entries.
lastn
Outside of the default set up, if you want to display a certain number of entries, you need to use the lastn attribute.
Changing <MTEntries> to <MTEntries lastn="7"> in the Main Index template will cause the index page to display the last 7 entries. Adding the attribute lastn="10" will cause the index page to display the last 10 entries, and so forth.
Previous Entries
Sometimes it is useful to show a list of the most recent entries that came before the entries that are displayed on your main index page. Rather than creating a super long page with 17 entries, you might want to display 7 entries and show a list of the 10 entries that came before, with links to their corresponding full entries.
To show a list of previous entries you need to employ the "offset" attribute. For example, if you wanted to show a list of the 10 entries that came before your 7 most recent entries, you would use a tag that looked like this:
The code that I have used on various blogs looks something like this:
This code I've placed right after the </MTEntries> tag that is the closing tag for the MTEntries section of code that governs the main display of entries on the page.

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if i want to show top 3 entries which are not under any category how will this be implemented.