Rav Nachman bar Yitzchak died in the year 4117. [And in the book Shenot Chaim, Parashat Metzora, he died in 666 according to the Seleucid era, which is the year 4115.] And he was in Pumbedita for 5 years [(Yuchsin in the order of Amoraim according to their times)].

Rav Chama became head in Nehardea after the death of Rav Nachman in the year 4117, and he reigned for 15 years and died in 4132 [(Tzemach David). And in Yuchsin in the letter of Rashbag, it was omitted, and this is a scribal error, correction and you shall find it].