This can be done with mailmerge with an Excel spreadsheet as the datasource.
Assuming that the XXXXX is the same, just have the numbers themselves in the
datasource and after you set up the mailmerge main document, remove the
<<Next Record>> field from all but the 9th, 17th etc. "labels"

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Hope this helps,
Doug Robbins - Word MVP
> I want to consecutively number labels on laser label
> sheets. The labels are 4 across and 20 down on an 8-
[quoted text clipped - 5 lines]
> the first 8 (or two rows) number XXXXX, the next 8 (or two
> rows) number XXXXX+1, etc on to Number XXXXX+300?