Magic number is a US sports term as it relates to the combined number of wins/losses that means team B cannot catch team A.
For us it's points rather than wins. No one on 48 points can get more than 63 points, those on 47 it's 62 and so on. As we're on 58 a combined 6 points won by us, or dropped by a team on 48, means they cannot catch us. 5 combined points for those on 47, and so on.
It amused me to do 6 7 rather than the real answer as i'm dead mature.