The last sucker loses 100%.
The site's operator's profit is 1% ... where did you get the 80% figure?
sorry, was mistaken there.
the profit is actually the first 1.0 + 1% of all wagers beginning with n=2.
here's an n=4 example. in this example, there is about an 80% payout, with the operator getting a 20% profit.
player A bets 1.0
player B bets 1.2, and 1.188 goes to player A.
player C bets 1.44, and 1.4256 goes to player B.
player D bets 1.728 and 1.71072 goes to player C
player D is the sucker and gets nothing.
total taken in = 5.368, total paid out 4.32432, total profit to operator 1.04368