Pagination is not working after refresh the page

Hii Everybody,

I have a problem with pagination.
I have a list of things in my list,like 5,10,20,30 …pages.
If i select the number of items to be displayed,it’s showing like 5 or
But after refreshing the page when i was in 10 or 20 pages like that ,it
is showing only 5 items per page.

Please post the exact code…

Thanks & Regards