My bad - confused by reading the chart - Adams was VP under Pres. Washington. Then Jefferson was VP under Pres. Adams. Then Aaron Burr was VP under Pres. Jefferson.
From the list I cannot see a single example of a President later serving as Vice President.
http://en.wikipedia.org/wiki/List_of_Vice_Presidents_of_the_United_States
Thank you, sir! I didn’t want to speak out of school, so I thought I’d asked. I do recall a lot of back and forth with President and VP back in the early days of our republic.