I have now no time to code but this is what I would do. My usual approach is to do gradually build it up recursively with backtracking. I would think that you would not see many of the 16! possible combinations in such a procedure. If one would use a string as the underlying data structure, then a regex should be possible to identify the bad patterns. My first thought was m/(....).*\1/ but that would not detect overlapping repetitions. But I am sure such a regex exists.

In reply to Re: (OT) A different kind of 'combinatorics' by hdb
in thread (OT) A different kind of 'combinatorics' by BrowserUk

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