Hi im trying to get maple to output different combinations from a list of elements ( without using any packages ). 

for example I have a list :

  here each { } is one element and I need to do combinations in 3's soo I want it to return:
  order doesnt matter and I dont want repetitions.
1. {2,8} {2,4,6,7,8} {4,6,8}
2. {2,8} {2,4,6,7,8} {1,4,8}
3. {2,8} {2,4,6,7,8} {1,4,8,9}