Using the Septuagint's expanded begetting ages from Genesis 5 and 11, including the second Cainan (Luke 3:36). Lifespans differ from the Masoretic Text in several post-Flood generations.
LXX vs. Masoretic — key differences: The Septuagint adds ~100 years to each pre-Flood begetting age (except Jared, Methuselah, Lamech) and ~100 years to each post-Flood begetting age. It also includes an additional generation — Cainan (son of Arpachshad) — confirmed in Luke 3:36. This pushes Adam from 4004 BC (Ussher/MT) to ~5508 BC (Byzantine/LXX), and the Flood from 2348 BC to ~3268 BC. From Abraham onward, the two traditions largely converge.