First, give it the abstract for a fresh paper that it couldn’t have been trained on, then see if it can come up with the same proofs to see if it can replicate the logic knowing the conclusion.
Second, you could give it all the papers cited in the intro and ask a series of leading questions like “based on this work, what new results can you derive”?
Finding a set of papers, whose results can be combined in a reasonable amount of time to make a new interesting result is itself a hard problem. This is often a thing Professors do for PhD students -- give them a general area to research and some papers to start reading.
It's still a contribution, but so much easier than just asking "Hey, choose a set of papers from which you can derive new interesting results"