Sequential Numbering

I have been tasked with coming up with a way to include a sequential number on the back of a photo. The number needs to begin with something like 001 and then continue indefinately. There would be four numbers on one single page and then as each subsequent page is printed the numbers need to continue to change. Example: Page #1 would have the numbers 001, 002, 003, 004 and then the second page would begin where the numbers left off on the first page. Example: Page #2 would have the numbers 005, 006, 007, 008. This numbering needs to continue indefinately so that we will constantly know how many pages had been printed. I hope this makes sense..., but more importantly..., I hope someone will be able to provide me with a formula which will complete this task.