Help!

I have a workbook with 13 tabs. Sometimes we have a need to up that to over
40 more, but all the new tabs would just be a copy of the other ones.

So I need a macro that would easily allow me to Add A user defined number of
additional tabs each being a copy of one of the originals. Each Tab would
also need to be named in succession (i.e., Tab 13, copies and pastes as Tab
14, then Tab 15, then Tab 16, then Tab 17, etc... up to as many as the user
specifies. CAN ANYONE Help?