Roger Hui gave a non-unique pair algorithm as below: Roger Hui rhui000 at shaw.ca Sat Feb 10 02:49:22 HKT 2007
Combinations are usually defined to have unique elements. http://www.jsoftware.com/jwiki/Essays/Combinations However, if non-unique is what you want: ; (i. ([ ,. }.)&.> <@i.) 4 0 0 0 1 0 2 0 3 1 1 1 2 1 3 2 2 2 3 3 3 How would I go about having non-unique triplets, quadruplets etc. ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
