Microsoft Office 2013 RDS Open Licenses

I have a customer who wishes to purchase Office 2013 Open licenses. We are also installing an RDS Server for remote access.

my Question is:

If we install the open license copy for 10 users on the RDS Server, is the client able to use the same license for their individual desktops when in this office?

Or would we require 10 Office 2013 Open Licenses + 10 Office 2013 Open Licenses = 20

Thanks!