Four people choose three, each can be five times, a total of six times.
When there are four people, each person has five times, which is equivalent to five times for four people. A total of 20 people, three at a time, can be divided into 6 groups.
Five people, five times each, a total of 25 times, can be divided into eight groups, represented by numbers.
123.451.234.512.345.123.455438+0.234. Only five streams appear four times, so n people appear five times, and the total number of groups divided into 5n times is 5n divided by 3 for rounding.