The Magic Number is:
Games in a season - (1st place team's wins + 2nd place team's losses) + 1
So if the Mets are 97 - 60 and the Phillies are in second place at 94 - 63, the Mets' Magic Number is 162 - (97 + 63) + 1 = 3. That means that any combination of 3 Met wins or Phillie losses would make it mathematically impossible for the Phillies to equal the Mets' win total. Magic Numbers are never expressed in the negative. Once a team's Magic Number hits 0 the other team is eliminated, and people stop discussing the Magic Number.