How do you get from 001 to 100, 002 to 200 and so on? Will it always be a mirror-image reversal from one to the other? Or is there some other pattern?
It looks as if what you want is a simple capture and reuse. But before we go any further we need to figure out exactly what you're doing. You don't really want to redirect from a short-and-simple URL such as "myname001" to a longer and uglier URL such as "abcd.php?id=100" do you? I tend to suspect that what you really want to do is rewrite: when the URL says such-and-such, quietly serve content from somewhere else.