I haven't played MM7 for some time but IIRC, the formula is:1. EXP needed for level 1 = 0
2. EXP needed for next level = EXP needed for current level + (next level) * 1000
Therefore:
level 1 - 0
level 2 - 2000
level 3 - 5000
level 4 - 9000
and so on.
Therefore, the formula for the needed EXP for a level N should be:
EXP = ( (N-1)*(N+2)/2 ) * 1000
For large N, the formula gives slightly more than
EXP ~ (N*N/2)*1000
IIRC, right clicking on your score in your personal screen will pop up a message box, which will tell you:
1. For which level you qualify currently.
2. How many EXP you need for next level
Therefore, computations aren't needed.