The abstract of the article is very short, and seems pretty clear to both of your questions.
This is what is special about them:
> a set of ten math questions which have arisen naturally in the research process of the authors. The questions had not been shared publicly until now;
I.e. these are problems of some practical interest, not just performative/competitive maths.
And this is what is know about the solutions:
> the answers are known to the authors of the questions but will remain encrypted for a short time.
I.e. a solution is known, but is guaranteed to not be in the training set for any AI.
The abstract of the article is very short, and seems pretty clear to both of your questions.
This is what is special about them:
> a set of ten math questions which have arisen naturally in the research process of the authors. The questions had not been shared publicly until now;
I.e. these are problems of some practical interest, not just performative/competitive maths.
And this is what is know about the solutions:
> the answers are known to the authors of the questions but will remain encrypted for a short time.
I.e. a solution is known, but is guaranteed to not be in the training set for any AI.