I could make a table for you, but you should be able to test the conditions and enter in the number of players and the ranks that you want to see.
Game Tab -> Points for playing (assuming you have your formula here) -> Test formula -> Test range
EDIT: I am making a table still, since I'm sure that you may have people asking if X people show and I place in rank Y, how many points do I earn. I'll have it be saved as an excel 2010 version, but if you need it to be the older version, let me know and I can save it that way too for you. I'll have it set for 50 people, 50 positions for you.