User blog comment:QuasarBooster/Bashicu matrix version 4 in Python!/@comment-35470197-20191109233117/@comment-35470197-20191110035429

The first 1 in (0,1,2,1,2) is not an ancestor of the rightmost 2 in the original definition. It might not effect the resulting rule to find the bad root for a standard expression, but seems to effect the bad part asceding rule if I am correct.