Some of us are still confused, mostly because it doesn't generally make sense to just add a bunch of rows to a table with only a sequence number filled in.
We still don't understand the purpose, Rows should only be added to a table when they contain some data that needs to be saved in a separate row. So far, your description doesn't rise to that standard. What other data goes into these rows and when is it entered? and why aren't the rows just entered when the other data is available?
There are reasons for doing stuff like this. For example, when a teacher gives a test, he might generate a record for each student who needs to take the test with null as the actual grade to indicate that the test has not yet been graded. The individual records serve as holding spots for the grades since EVERY student will eventually have a grade and rather than have an audit turn up a "missing" row at some future time, ALL rows are added now and the grade is filled in later. If the rows are not added "now", it will be difficult "later" to determine if a particular student's record is just not scored or if he was never supposed to take the test.