because it has been published making changes like that are not appropriate to publish.

• it never seems to work,
• it's going to invalidate 116 solutions.

Ditto.

Suggest the result table should be ordered by either age or by count.

Originally I had ORDER BY P.AGE but it seems tests are requiring the random order.

I think you shuld add order by clouse for those question that checked with "==" i have used distinct clouse in this question and that caused wrong ordering and havent found what is wrong that was annoying :)

I'm not a fan of the split/reverse/join chain that everyone else seems to have used. I am, however, a fan of the recursive solution.