Sure, it was the problem listed on this page: https://www.rain.org/~mkummel/stumpers/22sep00a.html. Basically it requires at least a bit of guess and checking, which made her feel as if she was doing it wrong since it seems like there would be a “formula” to do these that you could find if you did some algebra or something. I ended up writing a C++ program (yay, std::next_permutation) to brute force solutions but it could not find a pattern, especially if you try to increase the number of circles and look for patterns there.