Septuagint, see Genesis 5 and Genesis 11
http://www.ecmarsh.com/lxx/Genesis/index.htm

     Error    Septuagint Gap between Births

Adam   100      230
Seth   100      205
Enos   100      190 
Cainan 100      170
Mahal  100      165
Jared  0        162
Enoch  100      165
Methu  -20      167
Lamech 6        188
Noah   0        502
Shem   0        100
Arph   100      135
Cainan 130      130
Salah  100      130
Heber  100      134
Peleg  100      130
Ragau  100      132
Seruch 100      130
Nahor  150      179 

Adds an additional 586 years to Noah + 880 years to Abraham = 1466 extra years

Eight years were added to the birth of Jesus, causing Year One AD to become Year Nine AD.

Total = 1474 extra years (1475th)