I don't believe this can be accomplished without code. The reason is that your repeating table would need to have some way of adding rows to the repeating table. If the user enters 5, you'll need 5 rows in the repeating table.
Once added, you'd need to "Set a field's value". The problem is a rule to set a field's value would set all the rows for the one column.
For the first issue above, you could use the qRules command Insert.
For the second issue, you could use the qRules command SetValue.
This seems like a perfect scenario to try out qRules and see if it meets your needs. A free trial is available on Qdabra.com.
Of course, if you're experienced in writing code, you could write your own custom code to achieve this.
Hope this helps!