I'm not sure what you mean by 'in repeating table'?
Am I correct in thinking that you want to add another list item using web services similar to the example, ie with the same Title, but for each subsequent item the Seq number should increment?
If that is the case, I would add another Data Connection to the list, then add a couple of Rules wherever you need them where you set a query Field value prior to a 'Query For Data' Action so that you're only looking for the correct Title. Then you can use a 'Set a Fields Value' to Max(Seq) + 1 from that data source which will increment the Seq field prior to submitting it into the list via the web services.
Hope this helps