If player level < 35 (10 life per vitality.): X = V*10 + 40L*4 + 36

If player level ≥ 35 (level - 25 life per vitality.): X = V*(L-25) + (L-25)^2 *4 + 4036

Thus at level 60, each point of vitality adds 35 life. This does not including +40 base life and additional at level 1 at +4 life gained above per level 35, as illustrated in the functions above.