Advanced Dungeons and Dragons, 1st Edition 46
B/X Dungeons and Dragons 27
BECMI Dungeons and Dragons 50
Advanced Dungeons and Dragons, 2nd Edition 47
Dungeons & Dragons, Rules Cyclopedia Edition 49
Dungeons & Dragons, 4th Edition 9 + 1 = 10
Dungeons & Dragons, 5th Edition 37 - 2 = 35
5e put Dragonborn into the OGL. That's absolutely enormous, as far as I'm concerned. 4e made them a baseline race, but they were stuck behind the GSL, which is awful (and I absolutely grant that the GSL was one of the worst parts of 4e's existence). 5e means we can now, officially, include them in 3rd-party materials without resorting to silly loopholes.