This is going back, well, a year (!), but I wanted to give it a try! Here is the info over at Randy Seaver’s awesome blog, GeneaMusings.com:
In a nutshell, going back to your 11th generation (8th-great-GPs), you should have 1024 ancestors, or a total of 2047 people including yourself. I’ve went through my tree to see how many of those 2047 I can claim right now. And let’s just say, I’ve got my work cut out for me!