Thanks all.
On a similar note, how might one approach the problem of trying to essentially create all boolean lists of a particular size where there are at least n 1's in a row? So for example, if n is 3, 1 1 1 0 1 1 1 0 0 1 1 1 is accepted. I have a filter for checking whether any list is accepted, but not for generating all of them, specifically any lists where there are more than 2 groups of consecutive 1's. How could I either get this list 'directly' or generate every possible list (and then use my filter)? ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
