Numbers 1:44
44 iThese are those who were listed, whom Moses and Aaron listed with the help of the chiefs of Israel, twelve men, each representing his fathers’ house.
Deuteronomy 2:14–15
14 And the time from our leaving aKadesh-barnea until we crossed bthe brook Zered was thirty-eight years, cuntil the entire generation, that is, the men of war, had perished from the camp, as the Lord had sworn to them. 15 For indeed the hand of the Lord was against them, to destroy them from the camp, until they had perished.